Model: Macro-Tech 3600VZ

LEVEL LEVEL

ON

OFF

30

27

24

21

1815

12

9

6

3

0 ENABLECH1 CH2

ODEP

30

27

24

219

6

3

0

SIGNAL / IOC

1815

12

Model:Macro-Tech 3600VZ

Some models may be exported under the name Amcron.®

125113-18/97

© 1997 by Crown International, Inc., P.O. Box 1000, Elkhart, IN 46515-1000 U.S.A. Telephone: 219-294-8000.Fax: 219-294-8329. Macro-Tech amplifiers are produced by the Professional Audio Division of CrownInternational, Inc. Trademark Notice: SmartAmp™ and Grounded bridge™ are trademarks and Amcron,®

Crown,® Macro-Tech,® IOC,® ODEP,® IQ System,® P.I.P.® and TEF ® are registered trademarks of CrownInternational, Inc. Other trademarks are the property of their respective owners.

®

E106377

Applies to 120 VACNorth American Units

WORLDWIDESUMMARY OF WARRANTY

The Crown Audio Division of Crown International, Inc., 1718 WestMishawaka Road, Elkhart, Indiana 46517-4095 U.S.A. warrants to you,the ORIGINAL PURCHASER and ANY SUBSEQUENT OWNER of eachNEW Crown1 product, for a period of three (3) years from the date ofpurchase by the original purchaser (the “warranty period”) that the newCrown product is free of defects in materials and workmanship, and wefurther warrant the new Crown product regardless of the reason forfailure, except as excluded in this Crown Warranty.1 Note: If your unit bears the name “Amcron,” please substitute it for thename “Crown” in this warranty.

ITEMS EXCLUDED FROM THIS CROWN WARRANTYThis Crown Warranty is in effect only for failure of a new Crown productwhich occurred within the Warranty Period. It does not cover any productwhich has been damaged because of any intentional misuse, accident,negligence, or loss which is covered under any of your insurancecontracts. This Crown Warranty also does not extend to the new Crownproduct if the serial number has been defaced, altered, or removed.

WHAT THE WARRANTOR WILL DOWe will remedy any defect, regardless of the reason for failure (exceptas excluded), by repair, replacement, or refund. We may not elect refundunless you agree, or unless we are unable to provide replacement, andrepair is not practical or cannot be timely made. If a refund is elected, thenyou must make the defective or malfunctioning product available to usfree and clear of all liens or other encumbrances. The refund will be equalto the actual purchase price, not including interest, insurance, closingcosts, and other finance charges less a reasonable depreciation on theproduct from the date of original purchase. Warranty work can only beperformed at our authorized service centers. We will remedy the defectand ship the product from the service center within a reasonable timeafter receipt of the defective product at our authorized service center.

HOW TO OBTAIN WARRANTY SERVICEYou must notify us of your need for warranty service not later than ninety(90) days after expiration of the warranty period. All components must beshipped in a factory pack. Corrective action will be taken within areasonable time of the date of receipt of the defective product by ourauthorized service center. If the repairs made by our authorized servicecenter are not satisfactory, notify our authorized service centerimmediately.

DISCLAIMER OF CONSEQUENTIAL AND INCIDENTAL DAMAGESYOU ARE NOT ENTITLED TO RECOVER FROM US ANY INCIDENTALDAMAGES RESULTING FROM ANY DEFECT IN THE NEW CROWNPRODUCT. THIS INCLUDES ANY DAMAGE TO ANOTHER PRODUCTOR PRODUCTS RESULTING FROM SUCH A DEFECT.

WARRANTY ALTERATIONSNo person has the authority to enlarge, amend, or modify this CrownWarranty. This Crown Warranty is not extended by the length of timewhich you are deprived of the use of the new Crown product. Repairs andreplacement parts provided under the terms of this Crown Warranty shallcarry only the unexpired portion of this Crown Warranty.

DESIGN CHANGESWe reserve the right to change the design of any product from time to timewithout notice and with no obligation to make corresponding changes inproducts previously manufactured.

LEGAL REMEDIES OF PURCHASERNo action to enforce this Crown Warranty shall be commenced later thanninety (90) days after expiration of the warranty period.

THIS STATEMENT OF WARRANTY SUPERSEDES ANY OTHERSCONTAINED IN THIS MANUAL FOR CROWN PRODUCTS.

9/90

NORTH AMERICASUMMARY OF WARRANTY

The Crown Audio Division of Crown International, Inc., 1718 West MishawakaRoad, Elkhart, Indiana 46517-4095 U.S.A. warrants to you, the ORIGINALPURCHASER and ANY SUBSEQUENT OWNER of each NEW Crown prod-uct, for a period of three (3) years from the date of purchase by the originalpurchaser (the “warranty period”) that the new Crown product is free of defectsin materials and workmanship. We further warrant the new Crown productregardless of the reason for failure, except as excluded in this Warranty.

ITEMS EXCLUDED FROM THIS CROWN WARRANTYThis Crown Warranty is in effect only for failure of a new Crown product whichoccurred within the Warranty Period. It does not cover any product which hasbeen damaged because of any intentional misuse, accident, negligence, orloss which is covered under any of your insurance contracts. This CrownWarranty also does not extend to the new Crown product if the serial numberhas been defaced, altered, or removed.

WHAT THE WARRANTOR WILL DOWe will remedy any defect, regardless of the reason for failure (except asexcluded), by repair, replacement, or refund. We may not elect refund unlessyou agree, or unless we are unable to provide replacement, and repair is notpractical or cannot be timely made. If a refund is elected, then you must makethe defective or malfunctioning product available to us free and clear of all liensor other encumbrances. The refund will be equal to the actual purchase price,not including interest, insurance, closing costs, and other finance charges lessa reasonable depreciation on the product from the date of original purchase.Warranty work can only be performed at our authorized service centers or atthe factory. We will remedy the defect and ship the product from the servicecenter or our factory within a reasonable time after receipt of the defectiveproduct at our authorized service center or our factory. All expenses inremedying the defect, including surface shipping costs in the United States,will be borne by us. (You must bear the expense of shipping the productbetween any foreign country and the port of entry in the United States and alltaxes, duties, and other customs fees for such foreign shipments.)

HOW TO OBTAIN WARRANTY SERVICEYou must notify us of your need for warranty service not later than ninety (90)days after expiration of the warranty period. All components must be shippedin a factory pack, which, if needed, may be obtained from us free of charge.Corrective action will be taken within a reasonable time of the date of receiptof the defective product by us or our authorized service center. If the repairsmade by us or our authorized service center are not satisfactory, notify us orour authorized service center immediately.

DISCLAIMER OF CONSEQUENTIAL AND INCIDENTAL DAMAGESYOU ARE NOT ENTITLED TO RECOVER FROM US ANY INCIDENTALDAMAGES RESULTING FROM ANY DEFECT IN THE NEW CROWNPRODUCT. THIS INCLUDES ANY DAMAGE TO ANOTHER PRODUCT ORPRODUCTS RESULTING FROM SUCH A DEFECT. SOME STATES DONOT ALLOW THE EXCLUSION OR LIMITATIONS OF INCIDENTAL ORCONSEQUENTIAL DAMAGES, SO THE ABOVE LIMITATION OREXCLUSION MAY NOT APPLY TO YOU.

WARRANTY ALTERATIONSNo person has the authority to enlarge, amend, or modify this Crown Warranty.This Crown Warranty is not extended by the length of time which you aredeprived of the use of the new Crown product. Repairs and replacement partsprovided under the terms of this Crown Warranty shall carry only the unexpiredportion of this Crown Warranty.

DESIGN CHANGESWe reserve the right to change the design of any product from time to timewithout notice and with no obligation to make corresponding changes inproducts previously manufactured.

LEGAL REMEDIES OF PURCHASERTHIS CROWN WARRANTY GIVES YOU SPECIFIC LEGAL RIGHTS, YOUMAY ALSO HAVE OTHER RIGHTS WHICH VARY FROM STATE TO STATE.No action to enforce this Crown Warranty shall be commenced later thanninety (90) days after expiration of the warranty period.

THIS STATEMENT OF WARRANTY SUPERSEDES ANY OTHERSCONTAINED IN THIS MANUAL FOR CROWN PRODUCTS.

9/90Telephone: 219-294-8200. Facsimile: 219-294-8301

Telephone: 219-294-8200. Facsimile: 219-294-8301

THREE YEARFULL WARRANTY YEAR

3YEAR3

The information furnished in this manual does not include all of the details of design, production, or variations ofthe equipment. Nor does it cover every possible situation which may arise during installation, operation or main-tenance. If your unit bears the name “Amcron,” please substitute it for the name “Crown” in this manual. If youneed special assistance beyond the scope of this manual, please contact our Technical Support Group.

Crown Audio Division Technical Support GroupPlant 2 SW, 1718 W. Mishawaka Rd., Elkhart, Indiana 46517 U.S.A.

Phone: 800-342-6939 (North America, Puerto Rico and Virgin Islands) or 219-294-8200Fax: 219-294-8301 Fax Back (North America only): 800-294-4094 or 219-293-9200

Fax Back (International): 219-294-8100 Internet: http://www.crownintl.com

IMPORTANTCLASS 1 OUTPUT WIRING REQUIRED.

COMPLY WITH LOCAL ELECTRICAL CODESWHEN WIRING THIS DEVICE.

Printed onrecycled paper.

The lightning bolttriangle is used toalert the user to therisk of electric shock.

The exclamation pointtriangle is used to alert theuser to important operating ormaintenance instructions.

WARNINGTO REDUCE THE RISK OF ELECTRIC

SHOCK, DO NOT EXPOSE THISEQUIPMENT TO RAIN OR MOISTURE!

Magnetic FieldCAUTION! Do not locate sensitive high-gain equip-ment such as preamplifiers or tape decks directlyabove or below the unit. Because this amplifier hasa high power density, it has a strong magnetic fieldwhich can induce hum into unshielded devices thatare located nearby. The field is strongest just aboveand below the unit.

If an equipment rack is used, we recommend locatingthe amplifier(s) in the bottom of the rack and thepreamplifier or other sensitive equipment at the top.

C A U T I O NRISK OF ELECTRIC SHOCK

DO NOT OPEN

TO PREVENT ELECTRIC SHOCK DONOT REMOVE TOP OR BOTTOM

COVERS. NO USER SERVICEABLEPARTS INSIDE. REFER SERVICINGTO QUALIFIED SERVICE PERSON-NEL. DISCONNECT POWER CORDBEFORE REMOVING REAR INPUT

MODULE TO ACCESS GAIN SWITCH.

A V I SRISQUE DE CHOC ÉLECTRIQUE

N’OUVREZ PAS

À PRÉVENIR LE CHOC ÉLECTRIQUEN’ENLEVEZ PAS LES COUVERCLES.

IL N’Y A PAS DES PARTIESSERVICEABLE À L’INTÉRIEUR. TOUSREPARATIONS DOIT ETRE FAIRE PAR

PERSONNEL QUALIFIÉ SEULMENT.DÉBRANCHER LA BORNE AVANT

D’OUVRIR LA MODULE EN ARRIÈRE.

Macro-Tech 3600VZ Power Amplifier

Page 4

CONTENTS1 Welcome ............................................................................ 6

1.1 Unpacking ................................................................... 61.2 Features ...................................................................... 7

2 Facilities ............................................................................ 8

3 Installation ....................................................................... 103.1 Mounting ................................................................... 103.2 Cooling ...................................................................... 103.3 Wiring ........................................................................ 11

3.3.1 Stereo (Two-Channel) Operation ..................... 113.3.2 Bridge-Mono Operation .................................. 123.3.3 Parallel-Mono Operation .................................. 133.3.4 Input Connection............................................. 143.3.5 Output Connection .......................................... 163.3.6 Additional Load Protection .............................. 183.3.7 AC Power Requirements ................................. 18

4 Operation ......................................................................... 194.1 Precautions ............................................................... 194.2 Indicators .................................................................. 194.3 Protection Circuits ...................................................... 20

4.3.1 Output Device Emulation Protection (ODEP) ... 204.3.2 Standby Mode ................................................ 214.3.3 Transformer Thermal Protection ...................... 214.3.4 Circuit Breaker ................................................ 21

4.4 Controls ..................................................................... 224.5 Filter Cleaning............................................................ 23

5 Technical Information ..................................................... 245.1 Overview ................................................................... 245.2 VZ Power ................................................................... 24

5.2.1 Background .................................................... 245.2.2 The VZ Supply ................................................. 25

5.3 Circuit Theory ............................................................ 255.3.1 Stereo Operation ............................................. 255.3.2 Bridge-Mono Operation .................................. 275.3.3 Parallel-Mono Operation .................................. 27

6 Specifications ................................................................. 28

7 AC Power Draw and Thermal Dissipation ...................... 35

8 Accessories .................................................................... 368.1 P.I.P. Modules ............................................................ 368.2 Level Control Security Kit ........................................... 38

9 Service ............................................................................. 399.1 Worldwide Service ..................................................... 399.2 North American Service ............................................. 39

9.2.1 Service at a North American Service Center ... 399.2.2 Factory Service ............................................... 39


Page 5

ILLUSTRATIONS1.1 Macro-Tech 3600VZ Amplifier ................................................... 62.1 Front Facilities ........................................................................... 82.2 Rear Facilities ........................................................................... 93.1 Mounting Dimensions ............................................................. 103.2 Top View of a Rack-Mounted Unit ........................................... 103.3 Proper Air Flow in a Rack Cabinet ........................................... 103.4 Stereo Wiring .......................................................................... 113.5 Bridge-Mono Wiring ................................................................ 123.6 Parallel-Mono Wiring ............................................................... 133.7 Unbalanced Input Wiring ........................................................ 143.8 Balanced Input Wiring ............................................................ 143.9 Balanced and Unbalanced Phone Plugs ................................ 143.10 Subsonic Filter Capacitors ...................................................... 153.11 Unbalanced RFI Filters ........................................................... 153.12 Balanced RFI Filters ................................................................ 153.13 Wire Size Nomograph ............................................................. 163.14 Inductive Load (Transformer) Network .................................... 173.15 Loudspeaker Fuse Nomograph .............................................. 184.1 Indicators................................................................................ 194.2 Macro-Tech Indicator States ................................................... 204.3 Input Sensitivity and Ground Lift Switches .............................. 225.1 A Typical Power Supply .......................................................... 255.2 Music Waveforms are Complex .............................................. 255.3 VZ Supply in Parallel Mode ..................................................... 255.4 VZ Supply in Series Mode ....................................................... 255.5 Circuit Block Diagram ............................................................. 266.1 Minimum Power Matrix ............................................................ 316.2 Maximum Power Matrix ........................................................... 326.3 Typical Frequency Response .................................................. 336.4 Typical Damping Factor .......................................................... 336.5 Typical Output Impedance...................................................... 336.6 Typical Phase Response ......................................................... 346.7 Typical Crosstalk ..................................................................... 347.1 Power Draw, Current Draw and Thermal Dissipation ............... 358.1 Installing a P.I.P. Module .......................................................... 368.2 Installing an MA-LOCK Level Control Shaft Lock .................... 38


Page 6

Fig. 1.1 Macro-Tech 3600VZ Amplifier

1 WelcomeCongratulations on your purchase of the Macro-Tech®

3600VZ® professional power amplifier. It is the first au-dio amplifier to offer Crown’s patented Variable Imped-ance (VZ) power supplies. The new power supplies,along with new semiconductor technology, enable theMacro-Tech 3600VZ to pack more power into a mere31¦2 inches of vertical rack space than ever before. Be-cause it’s a Macro-Tech, you have the added benefit ofP.I.P.® compatibility for access to custom input mod-ules and ODEP® protection to keep the show goinglong after other amplifiers would fail (see the Section 8for available input modules).

This manual will help you successfully install and useyour new amplifier. We strongly recommend you readall instructions, warnings and cautions containedwithin. Be sure to read Sections 3.3.2 and 3.3.3 if youplan to use the amplifier in one of its two mono modes.Also for your protection, please send in your warrantyregistration card today and save your bill of sale sinceit is your official proof of purchase.

1.1 UnpackingPlease unpack and inspect your new amplifier for anydamage that may have occurred during transit. If dam-age is found, notify the transportation company imme-diately. Only you, the consignee, may initiate a claimwith the carrier for damage resulting during shipment.Crown will be happy to cooperate fully as needed. Savethe shipping carton as evidence of damage for theshipper’s inspection.

Even if the unit arrived in perfect condition, as most do,save all packing materials so you will have them if youever need to transport the unit. NEVER SHIP THE UNITWITHOUT THE FACTORY PACK.

LEVEL LEVEL

ON

OFF

30

27

24

21

1815

12

9

6

3

0 ENABLECH1 CH2

ODEP

30

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219

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SIGNAL / IOC

1815

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Page 7

1.2 FeaturesThe Macro-Tech 3600VZ amplifier uses the latest tech-nology and miniaturized design to deliver the highestpower and value for its size, weight and price. Crown’sgrounded bridge™ output and patented ODEP protec-tion circuitry combine to provide performance and reli-ability that surpass all conventional amplifier designs.Macro-Tech amplifiers also have an independent highvoltage power supply for each channel. This designprovides ultra-low crosstalk specifications and makesit possible to treat each channel as a separate ampli-fier. Features:

Crown’s grounded bridge™ circuitry generates in-credible voltage swings while avoiding stressful out-put transistor configurations common toconventional amplifiers. The results are lower dis-tortion and superior reliability.

Patented ODEP (Output Device Emulation Protec-tion) circuitry compensates for overheating andoverload to keep the amplifier working long afterothers would fail.

IOC® (Input/Output Comparator) circuitry immedi-ately alerts of any distortion exceeding 0.05%, pro-viding dynamic proof of performance.

P.I.P. (Programmable Input Processor) connectoraccepts accessories that tailor your amplifier to suitindividual applications.

Two mono modes (Bridge-Mono and Parallel-Mono)for driving a wide range of load impedances.

Very low harmonic and intermodulation distortionresult in the best dynamic transfer function in theindustry.

High damping factor provides superior control overlow frequency drivers for a clean, accurate low end.

An articulated VZ power supply for each channelprovides excellent crosstalk characteristics and thebest power matching to your load.

Full protection against shorted outputs, open cir-cuits, mismatched loads, general overheating, highfrequency overloads and internal faults; loud-speaker protection against low frequency and DCoutput.

Extra rugged, extruded aluminum front panel withODEP and Signal Presence/IOC indicators for eachchannel, as well as an Enable Indicator.

Separate voltage supplies for each channel providelow crosstalk and improved reliability.

Efficient heat sinks and a self-contained forced aircooling system dissipate heat quickly and evenly toprevent overheating, prolong component life anddeliver greater power output.

Balanced inputs and adjustable front panel levelcontrols.

31 detents in the level controls reduce the likelihoodof settings being inadvertently disturbed.

Ground lift switch to isolate chassis and phone jackaudio input grounds.

Multiple dual binding posts provide easy and ver-satile output connection.

Internal three position input sensitivity switch pro-vides settings of 0.775 volts and 1.4 volts for ratedoutput, and 26 dB voltage gain.

Mounts in a standard 19 inch (48.3 cm) equipmentrack with rear support, or units can be stacked.

All specifications are guaranteed for the duration ofthe warranty period.

Units in North America and other select countriesare covered by a three year “No-Fault” full warrantywhich completely protects your investment andguarantees its specifications.


Page 8

LEVEL LEVEL

ON

OFF

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A B C D D C B E F

Fig. 2.1 Front Facilities

2 FacilitiesA. Dust FilterThe dust filters remove large particles from the air atthe air intake. Check filters regularly to be sure they donot become clogged. The filter elements can be easilyremoved for cleaning by gently pulling them away fromthe front panel (see Sections 3.2 and 4.5).

B. Level ControlsThe level for each channel is set with these convenientcontrols mounted on the front panel. Each level controlhas 31 detents for precise adjustment (see Section4.4). A security option is available to prevent tamper-ing (see Section 8.2).

C. Signal / IOC IndicatorsThe presence of an audio signal and the distortion levelof each channel is represented by these green multi-function indicators. As signal presence indicators, theyflash with normal intensity in sync with the output audiosignal to indicate its presence. As IOC (Input/OutputComparator) indicators, they compare the waveformof the input signal to that of the output. They flashbrightly with a 0.1 second hold delay if there is a differ-ence (or distortion) of 0.05% or more. Another IOCfunction is to indicate input overload. If the input signalis too large the indicators will flash brightly (with a 0.5second hold delay) to indicate input clipping distor-tion. Note: The Channel 2 IOC indicator will stay on inParallel-Mono mode (refer to Section 4.2).

D. ODEP IndicatorsDuring normal operation of the Output Device Emula-tion Protection circuitry, these indicators glow brightlyto show the presence of reserve thermodynamic en-

ergy. They dim proportionally as energy reserves de-crease. In the event that energy reserves are depleted,the indicators turn off and ODEP proportionally limitsoutput drive so the amplifier can safely continue tooperate even under severe conditions. These indica-tors can also help to identify more unusual operatingproblems (see Section 4.2).

E. Enable IndicatorThis indicator lights when the amplifier has been “en-abled” or turned on, and AC power is available (seeSection 4.2).

F. Enable SwitchDepress this push-button to turn the amplifier on or off.When turned on, the output is muted for approximatelyfour seconds to protect your system from start-up tran-sients. (This delay can be changed. Contact the CrownTechnical Support Group for details.)

G. Power CordAll 120 VAC, 60 Hz North American units include aNEMA TT30P plug. These units also include 30-amp(10 AWG) line cord. Other units are equipped with apower cord and plug that is appropriate for the voltagerequirements of the amplifier.

H. Stereo/Mono SwitchThe three operating modes of this amplifier arecontrolled by this switch. Stereo mode is available fornormal two-channel operation. Bridge-Mono mode isavailable to drive a single load with an impedanceequal to or greater than 4 ohms. Parallel-Mono mode is


Page 9

Fig. 2.2 Rear Facilities

® INTERNATIONAL, INC.ELECTRONIC EQUIPMENT

ELKHART, IN 46517MADE IN U.S.A.

SERIAL NUMBER

0000

000000

G H I J K NKL N N N

IMPORTANT:CLASS 1 OUTPUTWIRING REQUIRED.

PUSH TO RESET

120 VAC / 60 Hz / 30 A

BRIDGE-MONO WIRINGTURN AMPLIFIER OFF.

SET STEREO/MONOSWITCH TOBRIDGE-MONO.

OUTPUT ACROSSRED TERMINALSONLY. (CH-1IS POSITIVE.)

PARALLEL-MONO WIRINGTURN AMPLIFIER OFF.

SET STEREO/MONO SWITCHTO PARALLEL-MONO.

ADD JUMPER (14 GAGEOR LARGER) ACROSSRED TERMINALS.

OUTPUT ACROSS CH-1TERMINALS ONLY.

1

2

3

4

1

2

3

CH-2 OUTPUT CH-1 OUTPUT

+

–

+

–

WARNING:PROTECTIVE COVERMUST BE IN PLACEOVER OUTPUT TERM-INALS BEFORE OPER-ATING AMPLIFIER.

UNBALANCEDINPUT WIRING

BALANCEDINPUT WIRING

THIS AMPLIFIER IS EQUIPPED WITH SELECTABLE INPUT SENSITIVITY. REMOVE P.I.P. MODULE TO ACCESS SENSITIVITY SWITCH.

CH-2 CH-1

+–

TIP

RING

SLEEVEGND

INPUT GROUND LIFT

LIFT

+ TIP

SLEEVEGND

(AFFECTS PHONE INPUTS ONLY.)

INPUTS

CAUTION: TURN OFF AMPLIFIER BEFORE CHANGING THIS SWITCH!

STEREO

BRIDGEMONO

PARALLELMONO

MAXIMUM OUTPUT: 1800WATTS PER CHANNEL INTO2 OHMS AT 1 KHz WITH NOMORE THAN 0.1% THD.

(MONO)

ProgrammableInput Processor (P.I.P.)

3

1 2GNDI N P U T I N P U T

C H - 2 C H - 1

PUSH PUSH

FX

M M

REG. U.S. PAT. OFF.4,330,8094,611,1804,788,452

100 VAC / 20 A / 50-60 Hz

120 VAC / 20 A / 50-60 Hz

230 VAC / 10 A / 50-60 Hz

available to drive a single load with an impedance lessthan 4 ohms. Important: Do NOT change this switchunless the amplifier is first turned off (seeSection 3.3).

I. Reset Buttons (PUSH TO RESET)These reset buttons are used to reset the breakers thatsafeguard the power supplies from overload (seeSection 4.3).

J. P.I.P. ModuleVersatile Programmable Input Processor modules pro-vide flexible expansion features that can be added tocustomize the amplifier. P.I.P. modules plug into theconnector inside the back panel of the amplifier. A P.I.P.module’s input connectors are placed in parallel withthe input phone jacks. The P.I.P.-FX is included as astandard feature to provide balanced XLR inputs. It hasno internal circuitry and can be used along with theinput phone jacks to facilitate “daisy chaining” multipleamplifiers. See Section 8 for a list of available P.I.P.modules.

K. Balanced Phone Jack InputsA balanced ¼ inch phone jack is provided for input toeach channel. They may be used with either balanced(tip, ring and sleeve) or unbalanced (tip and sleeve)input wiring (refer to Section 3.3). Because these in-puts are in parallel with the P.I.P. connector, they shouldnot be used as inputs if the installed P.I.P. has activecircuitry. Caution: The Channel 2 input should NOTbe used in either mono mode.

L. Ground Lift SwitchThe input signal ground may be isolated from the ACground with this switch to help prevent the hum cre-ated by unwanted ground loops. It affects only the in-put phone jacks. It has no affect on the P.I.P. module’sXLR input connectors. Activating the switch inserts animpedance between the sleeve of each phone inputjack and the circuit ground.

M. Balanced XLR InputsA balanced 3-pin female XLR connector is providedfor input to each channel by the P.I.P.-FX, a standardfeature of your amplifier. The XLR connectors are inparallel with the amplifier’s phone jacks. Because thereis no active circuitry on the P.I.P., the XLR connectorscan be used at the same time as the phone input jacksfor “daisy chaining” multiple amplifiers. Caution: TheChannel 2 input should NOT be used in either monomode.

N. Output JacksTwo pairs of dual binding posts are provided for theoutput of each channel so multiple loudspeakers canbe connected easily. The connectors accept bare wireor spade lugs.

Input Sensitivity SwitchThe three position input sensitivity switch inside theamplifier can be accessed by removing the P.I.P. mod-ule. Settings include 0.775 volts and 1.4 volts for ratedoutput, and 26 dB voltage gain (see Section 4.4).


Page 10

3 Installation3.1 MountingMacro-Tech amplifiers are designed for standard 19inch (48.3 cm) rack mounting and “stack” mountingwithout a cabinet. In a rack cabinet, it is best to mountthem one on top of the other. This provides efficient airflow and enables each unit to support the one above.

Important: Due to its weight, the back of the amplifiershould be supported.

Fig. 3.2 Top View of a Rack-Mounted Unit

If the air supply is unusually dusty, it may be necessarypre-filter it using commercial furnace filters, etc., to pre-vent rapid loading of the unit’s own air filter. Whenneeded, the unit’s filter can be cleaned with mild dishdetergent and water (see Section 4.5).

When mounting the amplifier in a rack cabinet, the sidewalls of the rack should be at least 2 inches (5 cm)away from the chassis as shown in Figure 3.2.

Tip: An easy way to verify adequate cooling is to ob-serve the ODEP indicators with the amplifier operatingunder worst-case conditions. If the indicators dim, ad-ditional cooling is recommended.

If your rack cabinet has a front door that could blockair flow to the amplifier’s air intakes, you must provideadequate air flow either with a grille in the door or bypressurizing the air behind the door. Wire grilles arerecommended over perforated panels because theyhave larger openings and cause less restriction.

A good choice for increased air flow behind a rackcabinet door is to mount one or more “squirrel cage”blowers in the rack (Option 1 below). The blower ismounted at the bottom of the rack so it blows outsideair into the space between the door and the front of theamplifiers. This blower should not blow air into or takeair out of the space behind the amplifiers. For rackswithout a door, mount a blower at the top of the rack soair is drawn out the back (Option 2 below). The blowermust provide air flow that exceeds the sum of the airflow required by the individual amplifiers.

SIDE VIEW

19 in48.3 cm

16 in40.6 cm

3.5 in8.9 cm

2.5 in6.35 cm

LEVEL LEVEL

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Fig. 3.3 Proper Air Flow in a Rack Cabinet

Fig. 3.1 Mounting Dimensions

3.2 CoolingNEVER block the amplifier’s side vents and front airintake. Under demanding conditions, there should bea minimum air flow of 45 cubic feet (1.3 cubic meters)per minute per amplifier. When mounted in a rack, allempty spaces should be covered with blank panels toprevent improper air flow. The amplifier’s air flow shouldbe augmented with a rack cooling system if its load isless than 4 ohms and it must operate at consistentlyhigh output levels as in concert sound reinforcement.

AIRFLOW

AIR FLOW

AMPLIFIER(TOP VIEW)

RACKCABINET

16 in40.6 cm

2 in(5 cm)MIN.

IMPORTANT: Be sure rear of amplifieris securely mounted to rack.

17 in43.2 cm

AIRFLOW

BLOWER(OPTION 2)

BLOWER(OPTION 1)

AIRFLOW

FRONTOF

RACK

DOOR

AIRFLOW

EQUIPMENTRACK

(SIDE VIEW)


Page 11

Fig. 3.4 Stereo Wiring

MIXER

CHANNEL 1LOUDSPEAKERS

–

+

–

+

–

+

–

+

CHANNEL 2LOUDSPEAKERS

CHANNEL 2

CHANNEL 1

STEREO MODE

Macro-Tech 3600VZ

CH-2 OUTPUT CH-1 OUTPUTI N P U T I N P U T

C H - 2 C H - 1

PUSH

FX

PUSH

CH-2 CH-1INPUTS

(MONO)

STEREO

BRIDGEMONO

PARALLELMONO

STEREO

BRIDGEMONO

PARALLELMONO


3.3 WiringThe following section describes common ways to in-stall your amplifier in a sound system. The input andoutput terminals are located on the rear panel. Pleaseuse care when making connections, selecting signalsources and controlling the output level. The load yousave may be your own! Crown assumes no liability fordamaged loads resulting from careless amplifier useor deliberate overpowering.

CAUTION: Always remove power from the unit andturn the level controls off when making or breakingconnections —especially if the load is a loudspeakersystem. This reduces the chance of loud blasts or dam-aged loudspeakers.

Macro-Tech amplifiers may be operated in one of threemodes (Stereo, Bridge-Mono, and Parallel-Mono) byswitching the Stereo/Mono switch on the rear panel.There are VERY IMPORTANT wiring differences be-tween these three modes which are discussed next.

3.3.1 Stereo (Two-Channel) OperationThe installation is very intuitive in Stereo mode. The in-put of Channel 1 feeds the output of the same channelas does the input of Channel 2. To put the amplifier intoStereo mode, first turn the amplifier off, then slide theStereo/Mono switch to the center position, and prop-erly connect the output wiring as shown in Figure 3.4.Two sets of binding posts are provided for each chan-nel to facilitate easy connection of multiple speakers toeach channel. Observe correct loudspeaker polarityand be very careful not to short the outputs of onechannel to that of the other channel while in Stereomode.

CAUTION: In Stereo mode, never parallel the twooutputs by directly tying them together or parallel-ing them with the output of any other amplifier.

Such connection does not result in increased poweroutput and can cause premature activation of the pro-tection circuitry to prevent overheating.


Page 12

Fig. 3.5 Bridge-Mono Wiring

BRIDGE-MONO MODE

Macro-Tech 3600VZ


C H - 2 C H - 1

PUSH

FX

PUSH

CH-2 CH-1INPUTS

(MONO)

STEREO

BRIDGEMONO

PARALLELMONO

STEREO

BRIDGEMONO

PARALLELMONO


MIXER

–

+

LOUDSPEAKER

DO NOT USECHANNEL 2

INPUTS.

DO NOTUSE BLACK

BINDINGPOSTS.

USE ONLY CHANNEL 1 INPUT

3.3.2 Bridge-Mono OperationBridge-Mono mode is intended for driving loads with anet impedance of 4 ohms or greater. (See Parallel-Mono if the load is less than 4 ohms.) Installing theamplifier in Bridge-Mono mode is very different fromthe other modes and requires special attention.

To put the amplifier in Bridge-Mono mode, turn theamplifier off and slide the Stereo/Mono switch towardthe right (as you face the back of the amplifier). Bothoutputs receive the signal from Channel 1 with the out-put of Channel 2 inverted so it can be bridged with theChannel 1 output. DO NOT USE THE CHANNEL 2 IN-PUT or the signal level and quality may be greatly de-graded. Keep the Level control of Channel 2 turnedcompletely down (counterclockwise).

Note: The input jack and level control for Channel 2 are

not defeated in Bridge-Mono mode. Any signal fed intoChannel 2 may work against and add to or distort thesignal in Channel 1.

Connect the load across the Channel 1 and 2 red bind-ing posts with the positive lead from the load attachingto a red post of Channel 1 and the negative lead of theload attaching to a red post of Channel 2 as shown inFigure 3.5. THE TWO BLACK BINDING POSTS ARENOT USED AND SHOULD NOT BE SHORTED. Theload must be balanced (neither side shorted toground).

CAUTION: Be certain all equipment (meters,switches, etc.) connected to the mono output isbalanced. To prevent oscillations, both sides of theline must be isolated from the input grounds.


Page 13

Fig. 3.6 Parallel-Mono Wiring

PARALLEL-MONO MODE

Macro-Tech 3600VZ


C H - 2 C H - 1

PUSH

FX

PUSH

CH-2 CH-1INPUTS

(MONO)

STEREO

BRIDGEMONO

PARALLELMONO

STEREO

BRIDGEMONO

PARALLELMONO


MIXER

USE ONLY CHANNEL 1 INPUT

LOUDSPEAKER

DO NOT USECHANNEL 2

INPUTS.

ADD A 14 GAUGE(OR LARGER)

JUMPER BETWEENTHE CHANNEL 1

AND 2 REDBINDING POSTS.

–

+

3.3.3 Parallel-Mono OperationParallel-Mono mode is used to drive loads with a totalimpedance of less than 4 ohms. (See Bridge-Mono ifthe load is 4 ohms or greater.) Installing the amplifier inParallel-Mono mode is very different from the othermodes and requires special attention.

CAUTION: Do not attempt to operate in Stereo orBridge-Mono mode until the Parallel-Mono jumperis first removed. Failure to do so will definitelycause inefficient operation, high distortion and ex-cessive heating.

To put the amplifier in Parallel-Mono mode, first turn itoff, then slide the Stereo/Mono switch to the left (as youface the back). Connect the input signal to Channel 1only. DO NOT USE THE CHANNEL 2 INPUT or the sig-nal level and quality may degrade greatly. Turn off theChannel 2 Level control (full counterclockwise).

Note: It is normal for the IOC indicator of Channel 2 tostay on in Parallel-Mono mode.

The input jack and Level control of Channel 2 are notdefeated in Parallel-Mono mode. Any signal fed intoChannel 2 may work against and add to or distort thesignal in Channel 1.

Install a jumper wire between the red binding posts ofboth Channel 1 and 2 that is at least 14 gauge in size.Then, connect the load to the output of Channel 1 asshown in Figure 3.6. The positive lead from the loadconnects to the red binding post of Channel 1 and thenegative lead from the load connects to the black bind-ing post of Channel 1.

CAUTION: Remove the jumper wire before chang-ing to any mode except Parallel-Mono.


Page 14

3.3.4 Input ConnectionBoth the balanced XLR and phone jack inputs have anominal impedance of 20 K ohms (10 K ohms with un-balanced wiring) and will accept the line-level outputof most devices. Female XLR input connectors are pro-vided on the standard P.I.P.-FX input module (otherP.I.P. modules are described in Section 8.1). Correctinput wiring will depend on two factors: (1) whether theinput signals are balanced or unbalanced, and (2)whether the signal source floats or has a ground refer-ence. Figures 3.7 and 3.8 show the recommendedconnection techniques for each type of signal source.

The amplifier’s built-in ¼-inch phone jack input con-nectors can be wired similarly for balanced or unbal-anced, floating or ground-referenced sources. Theyhave a standard tip-ring-sleeve (TRS) configuration:

Fig. 3.8 Balanced Input Wiring

Fig. 3.7 Unbalanced Input Wiring Fig. 3.9 Balanced and Unbalanced Phone Plugs

the tip is positive (+), the ring is negative (–) and thesleeve is ground (see Figure 3.9). Wiring for varioussources follows the XLR wiring guidelines shown in Fig-ures 3.7 and 3.8.

The phone jacks should not be used as inputs when aP.I.P. module with active circuitry is installed. The phonejacks are in parallel with the output of the P.I.P. module,so an input signal connected to the phone jacks canfeed backwards into the active circuitry of the P.I.P. andcause undesirable distortion. You can use the phonejacks for signal input with any of the following P.I.P.modules installed: P.I.P.-FX, P.I.P.-BB, P.I.P.-FMX, P.I.P.-FXQ and P.I.P.-FPX. All other P.I.P. modules have activecircuitry and should not be installed if you plan to con-nect input signals to the phone jacks. The phone jackscan always be used as “daisy chain” outputs to feedpost-processed signals from the P.I.P. to the inputs ofother amplifiers.

Please follow the instruction in Section 3.3.2 and 3.3.3if the amplifier will be used in either Bridge-Mono orParallel-Mono mode. Remember, do not use the Chan-nel 2 input in either mono mode.

Tw

in-le

ad s

hiel

ded

cabl

e

2-wire line cord(or battery power)

Shield connectedto ground terminal

3-wire grounded line cord(or other ground connection)

Shield is notconnectedat this end

Groundedsource


Input groundterminal not used

Groundedsource

Sin

gle-

cond

ucto

r co

axor

twis

ted

pair2-wire line cord

(or battery power)

Floatingsource

Shield connected to bothnegative (–) and groundinput terminals

+–

INPUT

Output

Floatingsource

+

3

1 2

+–

INPUT

+Output

3

1 2

+–

INPUT

Output +

3

1 2

+–

+Output

INPUT

3

1 2

3

1 2

+–

INPUT

2-wire line cord(or battery power)

Note: If two or more channels withthe same input ground reference

are driven from the samefloating source, connect

only one shield to thesource chassis.

Floatingsource


Shield not connectedat this end

Groundedsource

3

1 2

Output+–

+–

Output+–

INPUT

+–

SHIELD

BALANCED

+

SHIELD

UNBALANCED


Page 15

SOLVING INPUT PROBLEMSSometimes large subsonic (subaudible) frequenciesare present in the input signal. These can damageloudspeakers by overloading or overheating them. Toattenuate such frequencies, place a capacitor in se-ries with the input signal line. The graph in Figure 3.10shows some capacitor values and how they affect thefrequency response. Use only low-leakage paper, my-lar or tantalum capacitors.

For balanced input wiring use one of the examples inFigure 3.12. Filters A, B and C correspond to the un-balanced filters above. Filter D also incorporates thesubsonic filter described previously.

Fig. 3.11 Unbalanced RFI Filters

Another problem to avoid is the presence of large lev-els of radio frequencies or RF in the input signal. Al-though high RF levels may not pose a threat to theamplifier, they can burn out tweeters or other loadsthat are sensitive to high frequencies. Extremely highRF levels can also cause your amplifier to prematurelyactivate its protection circuitry, resulting in inefficientoperation. RF can be introduced into the signal by lo-cal radio stations and from the bias signal of manytape recorders. To prevent high levels of input RF, in-stall an appropriate low-pass filter in series with the theinput signal. Some examples of unbalanced wiring forlow-pass filters are shown in Figure 3.11.

Fig. 3.10 Subsonic Filter Capacitors

Fig. 3.12 Balanced RFI Filters

Tip: The P.I.P.-FX included with your amplifier hasplenty of room on its circuit board for input filters.

A third problem to avoid is hum . The two most com-mon sources of hum in an audio system are inductivecoupling and ground loops .

Inductive coupling can occur when input cables aresubjected to a magnetic field from a power cord orpower transformer. One way to prevent inductive cou-pling is to lace the input cables together along theirlength and route them as far away as possible frompower transformers and power cords. The use of

Input Wiring Tips

1. Use only shielded cable. Cables withhigher density shields are better. Spiralwrapped shield is not recommended.

2. When using unbalanced lines, keep thecables as short as possible. Avoid cablelengths greater than 10 feet (3 meters).

3. Do not run signal cables together withhigh-level wiring such as loudspeaker wiresor AC cords. This greatly lessens the chanceof hum or noise being induced into the inputcables.

4. Turn the entire system off before changingconnections. Turn level controls downcompletely before powering the system backup. Crown is not liable for damage incurredwhen any transducer or component isoverdriven.

+

–

Balanced In

910 Ω

.003fµ

.015fµ

.018fµ

1.8 mH

2.5 mH

A

C

B

.015fµ

1.8 mH

D

Balanced Out

+

–910 Ω

1.8 mH

2.5 mH

1.8 mH

+

–

Balanced In Balanced Out

+

–

+

–


+

–

+

–


+

–

0.47 Film

0.47 Film

1 Hz 10 Hz 100 Hz 1 kHz 10 kHz

dB

0

–5

–10

–15

1 fµ .1 fµ.05 f .01 fµ µ

Frequenc y

4 kHz 10 kHz 40 kHz 100 kHz

Frequenc y

dB

0

–10

–20

A

B

C

6 dB/octave

12 dB/octave

ToAmp

GND

ToAmp

GND

ToAmp

GND

Source

1.8 K ohm

.003fµ

.015fµ

.018fµ

3.9 mH

5 mH

600 ohmSource

R

600 ohmSource

R

A

C

B

Note: A low source impedance (R) can beincreased to 600 ohms with an a ppropriate resistor.


Page 16

shielded pair cable is another effective way to reduceor eliminate hum resulting from inductive coupling.

Ground loops often result when two or more devicesare improperly grounded. This causes undesirablestray currents that may produce hum in the output. Thebest way to avoid ground loops is to ensure that allsystem devices are plugged into the same power strip.In addition, make sure that all cable shields aregrounded at one end only.

Input and output grounds are sometimes tied togetherfor testing or metering. This can cause feedback os-cillation from load current in the test loop. In somesystems, even the AC power line may provide this feed-back path. Proper grounding, input isolation and isola-tion of common AC devices in the system is goodpractice.

3.3.5 Output ConnectionConsider the power handling capacity of your loadbefore connecting it to the amplifier. Crown is not liablefor damage incurred at any time due to overpowering.Fusing loudspeaker lines is highly recommended (seeSection 3.3.6). Also, please pay close attention to theprecautions provided in Section 4.1.

resistance increases. This is very important becausethe amplifier’s excellent damping factor can easily benegated by insufficient loudspeaker cables.

Use the nomograph in Figure 3.13 and the procedurethat follows to find the recommended wire gauge (AWGor American Wire Gauge) for your system.

Fig. 3.13 Wire Size Nomograph

Use Good Connectors

1. To prevent possible shorts, do not exposethe loudspeaker cable connectors.

2. Do not use connectors that might acci-dentally tie two channels together when mak-ing or breaking connections (for example, astandard three-wire stereo phone plug).

3. Connectors that can be plugged into ACpower receptacles should never be used.

4. Connectors with low current-carrying ca-pacity should not be used.

5. Connectors with any tendency to shortshould never be used.

HOW TO DETERMINEAPPROPRIATE WIRE GAUGE

It is important to use loudspeaker cables with sufficientgauge (thickness) for the length being used. The resis-tance introduced by inadequate loudspeaker cableswill reduce both the output power and the motion con-trol of the loudspeakers. The latter problem occurs be-cause the damping factor decreases as the cable

40

30

20

15

10

9

8

7

6

5

4

3

2

1

2

5

10

20

50

100

.04

.06

.1

.2

.4

.6

1

2

4

6

10

20

40

5

10

20

50

1

2

100

200

500

1000

2000

5000

8000

5000

1000

500

100

50

10

5

1

.5

.1

.05

.01

#28

#26

#24

#22

#20

#18

#16

#14

#12

#10

#8

#6

#4

#2

#0#00#0000

R

LOAD

RESISTANCE

(ohms)

L

R

R

DAMPING

FACTOR

L

S

R

SOURCE

RESISTANCE

(ohms)

S

2-COND.

CABLE

(feet)

COPPER

WIRE

(AWG)(ohms/1000 ft.)

Example Shown:R = 8 ohms; R = 0.016 ohms or D.F. = 500;Cable Length = 10 ft.; answer: #8 wire

L S

1

0.5

200

500

1,000

2,000

20,000

5,000

10,000

.01

.001

.02

.004

.006

.002

.0004

.0006

.0002

0.6

0.7

0.8

1.5

0.9


Page 17

2. Avoid using shielded loudspeaker cable.

3. Avoid long cable runs where the loudspeakercables from different amplifiers share a com-mon cable tray or cable jacket.

4. Never connect the amplifier’s input and outputgrounds together.

5. Never tie the outputs of multiple amplifiers to-gether.

6. Keep loudspeaker cables well separated frominput cables.

7. Install a low-pass filter on each input line (similarto the RF filters described in Section 3.3.4.

8. Install input wiring according to the instructionsin Section 3.3.4.

Another problem to avoid is the presence of large sub-sonic currents when primarily inductive loads areused. Examples of inductive loads are 70-volt trans-formers and electrostatic loudspeakers.

Inductive loads can appear as a short circuit at lowfrequencies. This can cause the amplifier to producelarge low-frequency currents and activate its protec-tion circuitry. Always take the precaution of installing ahigh-pass filter in series with the amplifier’s input wheninductive loads are used. A 3-pole, 18 dB per octavefilter with a –3 dB frequency of 50 Hz is recommended(depending on the application, an even higher –3 dBfrequency may be desirable). Such a filter is describedwith subsonic frequency problems in Section 3.3.4.

Another way to prevent the amplifier from prematurelyactivating its protection systems and to protect induc-tive loads from large low-frequency currents is to con-nect a 590 to 708 µF nonpolarized capacitor and4-ohm, 20-watt resistor in series with the amplifier’soutput and the positive (+) lead of the transformer. Thecircuit shown below uses components that are avail-able from most electronic supply stores.

Fig. 3.14 Inductive Load (Transformer) Network

1. Note the load resistance of the loudspeakers connectedto each channel of the amplifier. Mark this value on the“Load Resistance” line of the nomograph.

2. Select an acceptable damping factor and mark it on the“Damping Factor” line. Your amplifier can provide an ex-cellent damping factor of 1,000 from 10 to 400 Hz in Ste-reo mode with an 8-ohm load. In contrast, typical damp-ing factors are 50 or lower. Higher damping factors yieldlower distortion and greater motion control over the loud-speakers. A common damping factor for commercial ap-plications is between 50 and 100. Higher damping fac-tors may be desirable for live sound, but long cablelengths often limit the highest damping factor that can beachieved practically. (Under these circumstances,Crown’s IQ System® is often used so amplifiers can bemonitored and controlled when they are located very nearthe loudspeakers.) In recording studios and home hi-fi, adamping factor of 500 or more is very desirable.

3. Draw a line through the two points with a pencil, and con-tinue until it intersects the “Source Resistance” line.

4. On the “2-Cond. Cable” line, mark the length of the cablerun.

5. Draw a pencil line from the mark on the “Source Resis-tance” line through the mark on the “2-Cond. Cable” line,and on to intersect the “Annealed Copper Wire” line.

6. The required wire gauge for the selected wire length anddamping factor is the value on the “Annealed CopperWire” line. Note: Wire size increases as the AWG getssmaller.

7. If the size of the cable exceeds what you want to use,(1) find a way to use shorter cables, like using the IQ Sys-tem, (2) settle for a lower damping factor, or (3) use morethan one cable for each line. Options 1 and 2 will requirethe substitution of new values for cable length or dampingfactor in the nomograph. For option 3, estimate the effec-tive wire gauge by subtracting 3 from the apparent wiregauge every time the number of conductors of equalgauge is doubled. So, if #10 wire is too large, two #13wires can be substituted, or four #16 wires can be usedfor the same effect.

SOLVING OUTPUT PROBLEMSSometimes high-frequency oscillations occur whichcan cause your amplifier to prematurely activate itsprotection circuitry and result in inefficient operation.The effects of this problem are similar to the effects ofthe RF problem described in Section 3.3.4. To preventhigh-frequency oscillations:

1. Lace together the loudspeaker conductors foreach channel; do not lace together the conduc-tors from different channels. This minimizes thechance that cables will act like antennas andtransmit or receive high frequencies that cancause oscillation.

4-ohm, 20-wattResistor

590 to 708 µf Capacitor120 VAC, N.P.

+

–

InductiveLoad

+

–

FromAmplifierOutput


Page 18

3.3.6 Additional Load ProtectionBecause the amplifier generates enormous power, itmay be desirable to protect loudspeakers (or othersensitive loads) from damage due to excessive power.A common way to do this is to put a fuse in series withthe load. This may be accomplished by using a singlefuse to protect the entire system, or by fusing eachdriver.

Fuses help prevent damage due to prolonged over-load, but provide essentially no protection againstdamage from large transients. To minimize this latterproblem, use high-speed instrument fuses such as theLittlefuse 361000 series. If the loudspeaker is only sus-ceptible to damage caused by prolonged overload(such as overheating), use a fuse or circuit breakerhaving the same slow thermal response as the loud-speaker itself (such as a slow-blow fuse).

The nomograph in Figure 3.15 shows fuse size versusloudspeaker peak power rating. It can be used to de-termine the size of the required fuse.

3.3.7 AC Power RequirementsUse an isolated power receptacle whenever possiblewith adequate current. North American units areshipped with a 30 amp (10 AWG) line cord, a NEMATT30P plug and a NEMA TT30R receptacle. Interna-tional units are shipped without a plug connected tothe appropriate line cord. Line voltages of 10% or moreabove the specified voltage may damage the ampli-fier.

Fig. 3.15 Loudspeaker Fuse Nomograph

1.0

1.2

1.4

1.6

2.5

3

4

5

6

7

8

9

10

12

14

16

20

25

30

20

15

10

8

6

5

4

3

2

1.5

1

.8

.6

.5

.4

.3

.2

.15

.1

.08

3000

2000

1500

1000

800

600

400

300

200

150

100

80

60

40

30

20

15

10

8

6

4

3

2

1.5

1

LOU

DS

PE

AK

ER

IMP

ED

AN

CE

(ohm

s)

FU

SE

(am

ps)

LOU

DS

PE

AK

ER

RA

TIN

G

PE

AK

MU

SIC

PO

WE

R(w

atts

)(T

ypic

ally

4 ti

mes

the

cont

inuo

us a

vera

ge p

ower

)

Answer: Fuse = 1.5 A

2

40

Example: Impedance = 8 ohms.Peak Power = 75 W


Page 19

4 Operation4.1 PrecautionsAlthough the Macro-Tech 3600VZ is protected from ex-ternal faults, the following precautions should be fol-lowed for safety and optimum operation:

1. There are important differences among the Ste-reo, Bridge-Mono and Parallel-Mono operatingmodes (see Section 3.3).

2. WARNING: Do not change the position of theStereo/Mono switch unless the amplifier isfir st turned off.

3. CAUTION: In Parallel-Mono mode, a jumperis used between the Channel 1 and Channel2 red binding posts (amplifier outputs). Besure to remove this jumper for Bridge-Monoor Stereo mode; otherwise inefficient opera-tion, high distortion and excessive heatingwill occur. Check the Stereo/Mono switch onthe back panel for proper position.

4. Turn the amplifier off and unplug it fr om theAC mains before removing a P.I.P. card.

5. Use care when making connections, selectingsignal sources and controlling the output level.The load you save may be your own.

6. Do not short the ground lead of an output cableto the input signal ground. This may form aground loop and cause oscillations.

7. Operate the amplifier from AC mains of notmore than 10% variation above or below the se-lected line voltage and only the specified linefrequency.

8. Never connect the output to a power supplyoutput, battery or power main.

9. Tampering in the circuit by unqualified person-nel, or making unauthorized circuit changesmay be extremely dangerous and may invali-date the warranty.

Remember: Crown is not liable for damage that resultsfrom overdriving components in your system.

4.2 IndicatorsThe front panel has several helpful LED (light emittingdiode) indicators.

The amber Enable indicator is provided to show theamplifier has been turned on (or enabled) and that thelow-voltage power supply is working. It does not indi-cate the high voltage supply status. As a result, disrup-tion of the high voltage supplies has no effect on the

LEVEL LEVEL

ON

OFF

30

27

24

21

1815

12

9

6

3

0 ENABLECH1 CH2

ODEP

30

27

24

219

6

3

0

SIGNAL / IOC

1815

12

Enable indicator. This means that in the improbableevent that one or both channels overheat and cause ashut down of the high voltage power supply, the En-able indicator will remain on. However, the Signal/IOCindicator lights to show that the output waveform doesnot match the input.

The ODEP indicators provide a visual indication of theoperation of Crown’s patented Output Device Emula-tion Protection (ODEP) circuitry. This circuitry protectsthe amplifier output stages against heat damage byproportionally limiting the drive level to the outputstages. This enables the amplifier to operate safelyeven under severe operating conditions.

During normal operation, the ODEP indicators glowbrightly to indicate that the output stages are operatingwithin their thermal range (SOA - Safe Operating Area).However, if an output stage begins to overheat, theODEP circuitry proportionally limits the drive signal andthe LEDs dim. In the unlikely event that the amplifierexceeds the operating limits, ODEP shuts down theoutput stages and the indicators turn off. The indica-tors also turn off if the power supplies are put in standbymode.

Note: The high voltage power supplies will temporarilygo into standby mode if their transformers get too hotor if there is DC or heavy common-mode current in theoutput.

The green Signal/ IOC indicators provide the triplefunctions of Signal Presence, Distortion, and InputOverload indicators. As signal presence indicators,they flash with normal intensity in sync with the audiooutputs. As IOC (Input/Output Comparator) indicators,they flash brightly if there is any difference between theinput and output signal waveforms greater than 0.05%.Because transient distortion happens quickly, a 0.1second “hold delay” keeps the indicators on longenough to be easily noticed. This IOC function verifiesthe amplifier’s performance. As input overload indica-tors, they flash brightly with a 0.5 second hold delay

Fig. 4.1 Indicators


Page 20

Fig. 4.2 Macro-Tech Indicator States

when an input signal that is too large begins to causeearly clipping distortion at the input. Note: the Channel2 IOC indicator will stay on in Parallel-Mono mode.

4.3 Protection CircuitsMacro-Tech amplifiers provide extensive protectionand diagnostics capabilities. Protection systems in-clude ODEP, “standby”, and an AC circuit breaker.These features provide protection under any condi-tions.

ODEP

SIGNAL / IOC

OFF

OFF

There is no power to the amplifier and all indicators are off, including the Enable light.Possible reasons: (1) The amplifier’s enable switch is off. (2) The amplifier is not plugged into the powerreceptacle. (3) The AC circuit breaker has been tripped. (4) The amplifier’s low-voltage power supplyfuse has blown.

Indicator Status Amplifier Condition

ODEP

SIGNAL / IOC

ON

OFF

Normal operation for a channel with NO audio output. Possible reasons: (1) There is no input signal.(2) The input signal level is very low. (3) The channel’s level control is turned down.

ODEP

SIGNAL / IOC

ON

Normal

Normal operation for a channel with audio output. The ODEP indicator will remain at full intensityto show that there is reserve thermodynamic energy, and the signal/IOC indicator will flash with normalintensity to show that the channel has audio output.

ODEP

SIGNAL / IOC

ON

Bright

The channel’s output is exceeding 0.05% distortion. The input signal level is too high and IOC isreporting an input overload or output clipping.

ODEP

SIGNAL / IOC

OFF

Bright

The amplifier channel is in standby mode. Possible reasons: (1) A P.I.P. module like an IQ P.I.P.has turned off the channel’s high-voltage power supply. (2) The amplifier has just been turned on andis still in the four second turn-on delay. (3) The DC / low-frequency protection circuitry has beenactivated. (4) The fault protection circuitry has been activated. (5) The transformer thermal protectioncircuitry has been activated.

ODEP limiting has been activated. Possible reasons: (1) The amplifier’s air filters are blocked andneed to be cleaned. (2) There is insufficient cooling because of inadequate air flow or air that is too hot.(3) The load impedance for the channel is too low because the output is shorted or the amplifier isdriving too many loudspeakers for the selected stereo/mono mode. (4) The amplifier channel iscontinuously being driven to very high output levels.

ODEP

SIGNAL / IOC

OFF

Normal

ODEP limiting is about to begin. Possible reasons: (1) The amplifier’s air filters are blocked and needto be cleaned. (2) There is insufficient cooling because of inadequate air flow or air that is too hot.(3) The load impedance for the channel is too low because the output is shorted or the amplifier isdriving too many loudspeakers for the selected stereo/mono mode. (4) The amplifier channel iscontinuously being driven to very high output levels.

OR

OR

OR

Channel 2 only: The amplifier is in Parallel-Mono mode. The Channel 2 signal/IOC indicator alwaysturns on to full brightness whenever the amplifier’s stereo/mono switch is set to Parallel-Mono mode.

A channel’s circuit breaker has tripped. Transformer overload can cause a channel’s circuitbreaker to trip.

4.3.1 Output Device Emulation Protection (ODEP)Crown invented ODEP to solve two long standing prob-lems in amplifier design: To prevent amplifier shutdownduring demanding operation and to increase the effi-ciency of output circuitry.

To do this, Crown established a rigorous program tomeasure the safe operating area (SOA) of each outputtransistor before installing it in an amplifier. Crown alsodesigned intelligent circuitry to simulate the instanta-neous operating conditions of those output transistors.


Page 21

Its name describes what it does: Output Device Emu-lation Protection or ODEP. It not only simulates the op-eration of the output transistors but it also comparestheir operation to their known SOA. If ODEP sees thatmore power is about to be asked of the output devicesthan they are capable of delivering under the presentconditions, ODEP immediately limits the drive level untilit falls within the SOA. Limiting is proportional and keptto an absolute minimum—only what is required to pre-vent the possibility of output transistor damage.

This level of protection enables Crown to increase out-put transistor utilization while greatly increasing ampli-fier reliability.

Finally, this onboard intelligence is monitored in twoways. First, the front panel ODEP indicators showwhether the amplifier is functioning correctly or if ODEPis limiting the drive level. Second, ODEP data is fed tothe P.I.P. connector at the back of the amplifier so ad-vanced P.I.P. modules like the IQ-P.I.P. can use it tomake decisions and control the amplifier.

With ODEP you get the maximum power with the maxi-mum protection—the show goes on!

4.3.2 Standby ModeAn important part of a Macro-Tech amplifier’s protec-tion systems is standby mode. Standby protects theamplifier during potentially catastrophic conditions. Ittemporarily removes power from the high-voltage sup-plies to protect the amplifier and its loads. Standbymode can be identified using the indicator table in Fig-ure 4.2.

When you turn on the Enable switch, standby mode isactivated to provide turn-on protection. This power-updelay lets other system components settle before anysignals are amplified, and it provides some “random-ness” to the power-up sequence of multiple units whichreduces the system’s current demand during start-up.

If dangerous subsonic frequencies or direct current(DC) is detected in the amplifier’s output, the unit willactivate its DC/low-frequency protection circuitry andput the affected channels in standby. This protects theloads and prevents oscillations. The unit resumes nor-mal operation as soon as the amplifier no longer de-tects dangerous low-frequency or DC output. Althoughit is extremely unlikely that you will ever activate theamplifier’s DC/low-frequency protection system, im-proper source materials such as subsonic squarewaves or input overloads that result in excessivelyclipped input signals can activate this system.

The amplifier’s fault protection system will put an am-

plifier channel into standby mode in rare situationswhere heavy common-mode current is detected in achannel’s output. The amplifier should never outputheavy common-mode current unless its circuitry isdamaged in some way, and putting the channel instandby mode helps to prevent further damage.

The amplifier’s transformer thermal protection circuitryis activated where the unit’s transformer temperaturerises to unsafe levels. Under these abnormal condi-tions, the amplifier will put both channels into standbymode. In addition, the cooling fan will run at full speed.The amplifier will return to normal operation after thetransformer cools to a safe temperature. (For more in-formation on transformer thermal protection, refer tothe section that follows.)

4.3.3 Transformer Thermal ProtectionAll Macro-Tech amplifiers have transformer thermalprotection which protects the power supplies fromdamage under rare conditions where the transformertemperature rises too high. A thermal switch embed-ded in each channel’s power transformer removespower to that channel’s high-voltage power supply if itdetects excessive heat. The switch automatically re-sets itself as soon as the transformer cools to a safetemperature.

If your amplifier is operated within rated conditions, it isunlikely that you will ever see it activate transformerthermal protection. One reason is that ODEP keeps theamplifier working under severe conditions. Even so,higher than rated output levels, excessively low-imped-ance loads and unreasonably high input signals cangenerate excessive heat in the output devices. Thiscan overheat the transformer and activate its protec-tion system.

Macro-Tech amplifiers are designed to keep workingunder conditions where other amplifiers would fail. Buteven when the limits of a Macro-Tech are exceeded, itprotects itself—and your investment—from damage.

4.3.4 Circuit BreakerA circuit breaker is provided to prevent excessive cur-rent draw by the high-voltage power supplies. A resetbutton for the circuit breaker is provided on the backpanel. The rating of the circuit breaker for each ampli-fier model and each AC mains voltage is provided withthe specifications in Section 6. When operating withrated loads and output levels, this breaker should onlytrip in the incredibly rare instance of a catastrophicamplifier failure. Other protection systems such asODEP keep the amplifier safe and operational under


Page 22

0.77 V26 dB

SENSITIVITY SWITCH INSIDE ACCESS HOLE

INPUT GROUND LIFT SWITCH

1.4 V

UNBALANCEDINPUT WIRING

BALANCEDINPUT WIRING

THIS AMPLIFIER IS EQUIPPED WITH SELECTABLE INPUT SENSITIVITY. REMOVE P.I.P. MODULE TO ACCESS SENSITIVITY SWITCH.

CH-2 CH-1

+–

TIP

RING

SLEEVEGND

INPUT GROUND LIFT

LIFT

+ TIP

SLEEVEGND

(AFFECTS PHONE INPUTS ONLY.)

INPUTS

(MONO)

Fig. 4.3 Input Sensitivity and Ground Lift Switches

most other severe conditions. The breaker can alsotrip in situations where extremely low-impedance loadsand sustained high output levels result in current drawthat exceeds the breaker’s rating. Again, this shouldonly be possible when operating outside rated condi-tions or when an input signal is clipped severely.

4.4 ControlsThe Enable switch is located on the front panel so youcan easily turn the amplifier on and off. If you ever needto make wiring or other installation changes, don’t for-get to disconnect the power cord. The six steps listednext should be followed whenever you turn on the am-plifier.

1. Turn down the level of your audio source. Forexample, set your master mixer’s volume to –∞.

2. Turn down the Level controls of the amplifier (ifthey are not already down).

3. Turn on the Enable switch. The Enable indicatorbeside the switch should glow. During the foursecond mute delay which immediately follows,the Signal/IOC indicators may flash unpredict-ably and the ODEP LEDs will stay off. After themute delay, the ODEP indicators should comeon with full brilliance and the Signal/IOC indica-tors should function normally (remain off if nosignal is present; flash if a signal is present). Re-member, the Channel 2 Signal/IOC indicator re-mains on if the amplifier is in Parallel-Monomode.

4. After the mute delay, turn up the level of youraudio source to the maximum desired level.

5. Turn up the Level controls of the amplifier untilthe maximum desired sound level is achieved.

6. Turn down the level of your audio source to itsnormal range.

For ease of use, the Level controls are located on thefront panel. Each control has 31 detents for accuracy.To secure these controls, the Level Control Security Kitis available (see Section 8.2). Note: In Bridge-Mono orParallel-Mono mode, turn down the Channel 2 Levelcontrol and only use the Channel 1 control.

The Input Sensitivity Switch is located inside theback of the amplifier (Figure 4.3). It is set at the factoryto 0.775 volts for rated output into 8 ohms. It can alsobe switched to a sensitivity of 1.4 volts, or a fixed volt-age gain of 26 dB (4.8 volts for rated output).

How to change the input sensitivity:

1. Turn off the amplifier and disconnect its powercord from the AC mains power receptacle.

2. Remove the P.I.P. module (two screws).

3. Locate the sensitivity switch access hole insidethe chassis opening as shown in Figure 4.3. It islocated just above the phone jack inputs.

Note: The Sensitivity switch will not be visiblebecause it is mounted below the hole. Use yourlittle finger to reach it.

4. Set the switch to the desired position noted onthe access hole label. The position toward thefront panel sets the sensitivity to 1.4 volts forrated output, the middle position provides avoltage gain of 26 dB, and the position towardthe back panel sets the sensitivity to 0.775 voltsfor rated output.

5. Replace the P.I.P. module and restore the power.

The Input Ground Lift switch is located on the rearpanel (Figure 4.3) and can provide isolation betweenthe input signal ground and the AC ground. It affectsonly the phone jack inputs and has no affect on theinput connectors on the P.I.P. module. Sliding the switchto the left isolates or “lifts” the grounds by placing animpedance between the sleeve of each phone jackand the circuit ground.

When a P.I.P. module is plugged into the amplifier, onlythe noninverted and inverted signal lines are con-nected in parallel with the corresponding lines of theinput phone jacks. The signal grounds are not paral-leled. For example, XLR pins 2 and 3 are connected inparallel with the tip and ring of the correspondingphone jack. However, pin 1 of the XLR is not connectedin parallel with the sleeve of the phone jack.


Page 23

The Circuit Breaker Reset Buttons (PUSH TO RE-SET) are located on the back panel to protect thepower supplies against overload. If a circuit breakertrips, the Signal/IOC indicator of the affected channelturns on (the Enable indicator remains illuminated).

4.5 Filter CleaningDust filters are provided on the air intakes to the cool-ing system (Figure 2.1). If these filters becomeclogged, the unit will not cool as efficiently as it shouldand may produce lower-than-normal output levels dueto high heat diffuser temperature and activation of theODEP circuitry.

To clean, remove each of the filter elements by gentlypulling them away from the front panel. Clean with milddishwashing detergent and warm water. Replacementfilters may be ordered from the factory.

Dust filters are not 100% efficient—depending on thelocal environment, the internal heat sinks of the ampli-fier will benefit from periodic cleaning by a qualifiedtechnician. Internal cleaning information is availablefrom our Technical Support Group.


Page 24

5 Technical Information5.1 OverviewYour Macro-Tech VZ amplifier incorporates several newtechnological advancements including low-stress out-put stages, real-time computer simulation of outputtransistor conditions, advanced thermal management,a modular system for signal input and processing, andthe articulated VZ power supplies.

Custom protection circuitry limits temperature and cur-rent to safe levels while making the amplifier highly re-liable and tolerant of faults. Unlike many lesseramplifiers, it can operate at its voltage and current lim-its without self-destructing.

Real-time computer simulation is used to create ananalogue of the junction temperature of the output tran-sistors (hereafter referred to as the “output devices”).Current is limited only when the device temperaturebecomes excessive—and just by the minimum amountnecessary. This patented approach is called ODEP orOutput Device Emulation Protection. It maximizes theavailable output power and eliminates overheating, themajor cause of output device failure.

The amplifier is protected from all common hazardsthat plague high-power amplifiers including shorted,open or mismatched loads; overloaded power sup-plies, excessive temperature, chain-destruction phe-nomena, input overload damage and high frequencyblowups. The unit protects loudspeakers from DC inthe input signal, DC in the output, turn-on and turn-offtransients, and it detects and prevents unwanted DCin the output. The amplifier is also protected from inter-nal faults.

The patented four-quadrant topology used in thegrounded output stages is called the grounded bridge.The grounded bridge topology takes full advantage ofthe power supplies delivering peak-to-peak voltagesto the load that are twice the voltage seen by the out-put devices and twice the voltage generated by thepower supplies.

The grounded bridge topology is ground-referenced.Because the required current exceeds the limits ofpresently available components, composite outputdevices are constructed to function as gigantic NPNand PNP devices. Each output stage has two compos-ite NPN and two composite PNP devices.

The devices connected to the load are referred to as“high-side NPN and PNP” and the devices connectedto ground are referred to as “low-side NPN and PNP.”

Positive current is delivered to the load by increasingconductance simultaneously in the high-side NPN andlow-side PNP stage, while decreasing conductance ofthe high-side PNP and low-side NPN in synchrony.

The two channels may be used together to double thevoltage (Bridge-Mono) or the current (Parallel-Mono)presented to the load. This feature gives the user flex-ibility in maximizing the power available to the load.

A wide-bandwidth multiloop design is used for state-of-the-art compensation. This produces ideal behav-ior, and results in ultra-low distortion values.

Aluminum extrusions have been widely used for heatsinks in power amplifiers due to their low cost and rea-sonable performance. However, measured on a wattsper pound or watts per volume basis, the extrusiontechnology doesn’t perform nearly as well as the heatsink technology developed for Macro-Tech power am-plifiers.

Our heat sinks are fabricated from custom convolutedfin stock that provides an extremely high ratio of areato volume, or area to weight. All power devices aremounted directly to massive heat spreaders that areelectrically alive. Electrifying the heat spreaders im-proves thermal performance by eliminating the insulat-ing interface underneath the power devices. Thechassis itself is used as part of the thermal circuit, andthis maximizes utilization of the available resources.

5.2 VZ PowerVZ means Variable Impedance. It is the name ofCrown’s patented articulated power supply technology.This technology is what makes it possible to pack suchtremendous power into Crown’s Macro-Tech 3600VZand 5000VZ amplifiers.

5.2.1 BackgroundA power supply must be large enough to handle themaximum voltage and current necessary for the ampli-fier to drive its rated power into a specified load. In theprocess of fulfilling this requirement, conventionalpower supply designs produce lots of heat, are heavy,and take up precious real estate. And it is no secretthat heat is one of a power amplifiers worst enemies.Consider the circuit in Figure 5.1.

According to Ohm’s Law, the bigger the power supply,the more heat the power transistors must dissipate.


Page 25

POWERTRANSISTOR

POWERTRANSISTOR

SPEAKERLOAD

POWERSUPPLY

+

–

Fig. 5.1 A TypicalPower Supply

The power transis-tors stay coolerand are not forcedto needlessly dissi-pate heat. This isthe normal operat-ing mode of the VZpower supply.

When the voltagerequirements arehigh, VZ suppliesswitch to a seriesmode which pro-duces higher volt-age and less

current. The amplified output signal never misses abeat and gets full voltage when it needs it—not when itdoesn’t need it.

Sensing circuitry watches the voltage of the signal todetermine when to switch VZ modes. The switchingcircuitry is designed to prevent audible switching dis-tortion to yield the highest possible dynamic transferfunction—you hear only the music and not the ampli-fier. You get not only the maximum power with the maxi-mum safety, but you also get the best power matchingto your load.

5.3 Circuit TheoryEach channel is powered by its own power transformer,T100 or T200. Both channels share TF-1, a low voltagetransformer. The secondary outputs of each trans-former are full-wave rectified by heavy duty bridge rec-tifiers and are filtered by large computer gradecapacitors. A thermal switch embedded in each trans-former protects them from overheating.

The low voltage transformer TF-1 uses a separate fanmotor winding. The TF-1 output is rectified by diodesD1-4 delivering an unregulated 24 volts. Monolithicregulators U1-2 provide a regulated ±15 volts.

5.3.1 Stereo OperationFor simplicity, the discussion of stereo operation willrefer to one channel only. Mono operation will be dis-cussed later.

See the block diagram in Figure 5.5 and the schemat-ics at the back of this manual.

The input signal at the phone jack passes directly intothe balanced gain stage (U104-C,D). Use of a P.I.P.module for input signal causes the input signal to passthrough the P.I.P. and then to the balanced gain stage.

Also, the lower the re-sistance of the powertransistors, the morevoltage you can deliverto the load. But whenyou lower the resis-tance of the transistors,you increase the cur-rent passing throughthem, and again in-crease the amount ofheat they must dissi-pate.

5.2.2 The VZ SupplyAn articulated power supply like VZ avoids much ofthis problem by reducing the voltage applied to thetransistors when less voltage is needed. Reducing thevoltage reduces the heat, so the amplifier runs coolerand more power can be packed in safely.

The VZ supply is divided into segments to better matchthe voltage and current requirements of the power tran-sistors. Remember that audio signals like music arecomplex waveforms.

Fig. 5.2 Music Waveforms Are Complex

For music, the average level is always much less thanthe peak level. This means a power supply does notneed to produce full voltage all the time.

POWERTRANSISTOR

POWERTRANSISTOR

SPEAKERLOAD

VZSTAGE

+

–

VZSTAGE

+

–

VZ POWER SUPPLY

Fig. 5.4 VZ Supply inSeries Mode

Fig. 5.3 VZ Supply in Parallel Mode

The VZ supply isdivided into twoparts. When thevoltage require-ments are nothigh, it operatesin a parallelmode to pro-duce less volt-age and morecurrent.

POWERTRANSISTOR

POWERTRANSISTOR

SPEAKERLOAD

VZSTAGE

+

–

VZSTAGE

+

–

VZ POWER SUPPLY


Page 26

Fig. 5.5 Circuit Block Diagram

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POW

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DC/L

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POW

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1/4"

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ON

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Page 27

The balanced gain stage (U104-C,D) causes bal-anced-to-single-ended conversion to take place usinga difference amplifier. From there, gain can be con-trolled with a potentiometer. The error amp (U104-A)amplifies the difference between the output signal andthe input signal from the gain pot, and drives the volt-age translator stage.

The voltage translator stage channels the signal to theLast Voltage Amplifiers (LVAs), depending on the sig-nal polarity, from the error amp U104-A. The +LVA(Q105,Q125) and the –LVA (Q110,Q126), with theirpush-pull effect through the bias servo Q318, drive thefully complementary output stage.

The bias servo Q318 is thermally coupled to the heatsink, and sets the quiescent bias current in the outputstage to lower the distortion in the crossover region ofthe output signal. D301, D302, D303, and D304 areused to remove the charge on the unused portion ofthe output stage, depending on the polarity of the out-put signal.

With the voltage swing provided by the LVAs, the sig-nal then gains current amplification through theDarlington emitter-follower output stage.

The bridge-balanced circuit (U104-B) receives a sig-nal from the output of the amplifier, and differences itwith the signal at the Vcc supply. The bridge-balancedcircuit then develops a voltage to drive the bridge-bal-anced output stage. This results in the Vcc supply hav-ing exactly one half of the output voltage added to theirquiescent voltage. D309, D310, D311 and a trimmerresistor set the quiescent current point for the bridge-balanced output stage.

The protection mechanisms that affect the signal pathare implemented to protect the amplifier under real-world conditions. These conditions are high instanta-neous current, excessive temperature, and operationof the output devices outside safe conditions.

Q107 and Q108 act as a conventional current limiter,sensing current in the output stage. The allowable cur-rent level is also adjusted as a function of voltage.When current at any one instant exceeds the designcriteria, the limiters remove the drive from the LVAs,thus limiting current in the output stage to a safe level.

To further protect the output stages, a specially devel-oped ODEP (Output Device Emulation Protection) cir-cuit is used. It produces an analog output proportional

to the always-changing safe operating area of the out-put transistors. This output controls the translator stageby removing any drive that exceeds the safe operatingarea of the output devices.

Thermal sensor S100 gives the ODEP circuits vital in-formation on the operating temperature of the heatsinkon which the output devices are mounted.

Should the amplifier fail in such a way that would causeDC across the output lead, the DC protection circuitsenses this on the negative feedback loop and shutsdown the power supply until the DC is removed.

5.3.2 Bridge-Mono OperationBy setting the back panel Stereo/Mono switch toBridge-Mono, the user can convert the Macro-Tech intoa Bridge-Mono amplifier. With a signal applied to theChannel 1 input and the load between the red bindingposts on the back panel, a double voltage output oc-curs.

The Channel 1 output feeds the Channel 2 error ampU204-A. Since there is a net inversion, Channel 2 out-put is out of polarity with Channel 1. This producestwice as much voltage across the load. Each of thechannel’s protection mechanisms work independentlyif a fault occurs.

5.3.3 Parallel-Mono OperationWith the Stereo/Mono switch set to Parallel-Mono, theoutput of Channel 2 is paralleled with that of Chan-nel 1. A suitable high-current-handling jumper must beconnected across the red binding posts to gain thebenefits of this mode of operation.

The signal path for Channel 1 is the same as previ-ously discussed, except that Channel 1 also drives theoutput stage of Channel 2. The balanced input, erroramp, translators and LVAs of Channel 2 are discon-nected and no longer control the Channel 2 outputstage. The Channel 2 output stage and protectionmechanisms are also coupled through S1 and functionas one.

In Parallel-Mono mode, twice the current of one chan-nel alone can be obtained. Since the ODEP circuit ofChannel 2 is coupled through S1, this gives added pro-tection if a fault occurs in the Channel 2 output stage.The ODEP circuit of Channel 2 will limit the output ofboth output stages by removing the drive from theChannel 1 translator stages.


Page 28

6 SpecificationsThese specifications apply to 120 VAC units in stereomode with 8 ohm loads and an input sensitivity of 26 dBunless otherwise specified.

120 VAC, 60 Hz Units: These units are equipped with trans-formers rated for 120 VAC, 60 Hz power.

International Units: These units are equipped with trans-formers for either 100 VAC, 50/60 Hz, or 230 VAC, 50/60 Hzpower.

PerformanceFrequency Response: ±0.1 dB from 20 Hz to 20 kHzat 1 watt. See Figure 6.3.

Phase Response: ±10° from 10 Hz to 20 kHz at 1watt. See Figure 6.6.

Signal-to-Noise Ratio: Greater than 105 dB belowrated output (20 Hz to 20 kHz, A-weighted); 100 dBbelow rated output (20 Hz to 20 kHz, no weighting).

Harmonic Distortion (THD): At rated output, less than0.05% from 20 Hz to 1 kHz increasing linearly to lessthan 0.1% at 20 kHz.

IM Distortion (IMD): Less than 0.05% from 368 milli-watts to full rated output.

Damping Factor: Greater than 1,000 from 10 Hz to400 Hz. See Figure 6.4.

Crosstalk: See Figure 6.7.

Slew Rate: Greater than 30 volts per microsecond.

Voltage Gain: (At maximum output) 20:1 ±3% or 26dB ±0.25 dB at +26 dB sensitivity, and 124.6:1 ±12%or 41.9 dB ±1.0 dB at 0.775 volt sensitivity.

PowerOutput Power:Note: Maximum average watts per channel (unless inMono mode) at 1 kHz with 0.1% or less THD.

120 VAC, 60 Hz Units:Stereo mode with both channels driven:

1800 watts into 2 ohms.1565 watts into 4 ohms.1120 watts into 8 ohms.

Bridge-Mono mode: 3505 watts into 4 ohms. 3140 watts into 8 ohms.

Parallel-Mono mode: 3555 watts into 1 ohm. 3190 watts into 2 ohms.

100 VAC International Units:Stereo mode with both channels driven:

1460 watts into 2 ohms.1300 watts into 4 ohms. 980 watts into 8 ohms.


Parallel-Mono Mode 2820 watts into 1 ohm. 2585 watts into 2 ohms.









Load Impedance: Rated for 16, 8, 4, and 2 ohm useonly. Safe with all types of loads, even reactive ones.

AC Power Requirements: 100 VAC, 50/60 Hz; 120VAC, 50/60 Hz; and 230 VAC, 50/60 Hz units are avail-able. 230 VAC, 50/60 Hz units can be used with 220and 240 VAC. All versions draw 90 watts or less at idle.100 and 120 VAC units can draw up to 30 amps ofcurrent; 230 VAC units can draw up to 15 amps. Referto the back panel for your unit’s specifications. Referto Section 7 for more details.

It is extremely important to provide sufficient AC powerto the amplifier. Power amplifiers cannot create en-ergy—they must have the proper voltage and currentto deliver the clean rated power you expect.


Page 29

ControlsEnable: A front panel push button used to turn theamplifier on and off.

Level: A 31-position detented rotary attenuator foreach channel located on the front panel used to con-trol the output level.

Stereo/Mono: A three-position back panel switch usedto select Stereo, Bridge-Mono or Parallel-Mono opera-tion.

Sensitivity: A three-position switch located inside theP.I.P. compartment used to select one of three inputsensitivities for both channels: 0.775 volts or 1.4 voltsfor standard 1 kHz power or a voltage gain of 26 dB.

Input Ground Lift: A two position back panel switchused to isolate the phone jack signal grounds from thechassis (AC) ground.

Reset: A back panel button for each channel used toreset the corresponding power supply. 100 and120 VAC units have 15 amp circuit breakers. 230 VACunits have 7.5 amp circuit breakers.

IndicatorsEnable: This amber indicator is on when the amplifieris switched on to show that the low voltage power sup-ply is operating.

Signal / IOC: Two green indicators flash with mediumintensity in sync with the amplifier’s outputs to showsignal presence. In the unlikely event the output wave-form differs from that of the input by 0.05% or more,they flash brightly to indicate distortion. As sensitivedistortion indicators they provide proof of performance.Note: It is normal for the Channel 2 IOC indicator toremain on in Parallel-Mono mode.

ODEP: Each channel has a multifunction LED (lightemitting diode) indicator that shows the channel’s en-ergy reserve status. Normally, the LEDs are brightly litto show that reserve energy is available. In the rareevent that a channel has little reserve, its indicator dimsin proportion to ODEP limiting. An ODEP indicator mayalso turn off under other, more unusual circumstances(see Section 4.2).

Input/OutputInput Connector: Balanced ¼-inch phone jacks onchassis and internal P.I.P. connector. (Balanced 3-pinXLR connectors are provided on the P.I.P.-FX which isa standard feature.)

Input Impedance: Nominally 20 K ohms, balanced.Nominally 10 K ohms, unbalanced.

Input Sensitivity: Switchable between 0.775 V (un-balanced) for rated output or a fixed voltage gain of 26dB. (See subsection 4.4 for more information.)

Output Connector: Color-coded dual binding posts(banana jacks).

Output Impedance: Less than 10 milliohms in serieswith less than 2 microhenries. See Figure 6.5.

DC Output Offset: (Shorted input) ±10 millivolts.

Output SignalStereo: Unbalanced, two-channel.

Bridge-Mono: Balanced, single-channel. Channel 1controls are active; Channel 2 controls are inactive andnot removed from operation.

Parallel-Mono: Unbalanced, single-channel. Channel1 controls are active; Channel 2 controls are inactivebut not removed from operation.

ProtectionMacro-Tech amplifiers are protected against shorted,open or mismatched loads; overloaded power sup-plies; excessive temperature, chain destruction phe-nomena, input overload damage and high-frequencyblow-ups. They also protect loudspeakers from input/output DC and turn-on/turn-off transients.

If unreasonable operating conditions occur, the pat-ented ODEP circuitry proportionally limits the drive levelto protect the output devices, particularly in the caseof elevated temperature. Transformer overheating re-sults in a temporary shutdown of the offending chan-nel. When it has cooled to a safe temperature, thetransformer automatically resets itself. Controlled slewrate voltage amplifiers protect against RF burnouts,and input overload protection is provided by current-limiting resistance at the input.

Turn On: The four second turn-on delay prevents dan-gerous turn-on transients. Turn-on occurs at zerocrossing of the AC waveform, so power sequencersare rarely needed with multiple units. Note: The turn-ondelay time may be changed. Contact Crown’s Techni-cal Support Group for details.

Circuit Breaker: Circuit breaker current ratings varybased on the AC operating power.


Page 30

ConstructionDurable black powder coated steel chassis and alumi-num front panel with Lexan overlay; specially designed“flow-through” ventilation from front to side panels.

Cooling: Forced-air with custom heat diffusers andpatented circuitry to promote uniform dissipation.

Dimensions: 19 inch (48.3 cm) standard rack mount(EIA Std. RS-310-B), 3.5 inch (8.9 cm) height, 16 inch(40.6 cm) depth behind mounting surface and 2.5inches (6.4 cm) in front of mounting surface.

Approximate Weight: Center of gravity is 6 inches(15.2 cm) behind the front mounting surface.

120 VAC, 60 Hz Units:Net weight 55 lbs, 1.5 ounces (25.0 kg); shippingweight 63 lbs, 10 ounces (28.9 kg).

100 VAC International Units:Net weight 54 lbs, 5 ounces (24.7 kg); shippingweight 63 lbs, 0.5 ounces (28.6 kg).

120 VAC International Units:Net weight 55 lbs, 1.5 ounces (25.0 kg); shippingweight 63 lbs, 10 ounces (28.9 kg).

230 VAC International Units:Net weight 53 lbs, 6 ounces (24.2 kg); shippingweight 61 lbs, 15 ounces (28.1 kg).


Page 31

Crown specifications are guaranteed for three years.In an effort to provide you with as much information as possible about the high power-producing capabilities of your amplifier, we havecreated the following power matrices.

Minim um Guaranteed P ower SpecificationsCrown’s minimum power specifications represent the absolute smallest amount of output power you can expect from your amplifierwhen it is driven to full output under the given conditions. Some spaces in each matrix may be left blank because the same guaranteeis not provided for those conditions—however, your amplifier will perform well under all conditions listed in each matrix.

When measuring power, 0.1% THD appears to be the industry standard for distortion. Two of the maximum average powerspecifications shown in each minimum power matrix are measured at 0.1% THD so you can easily compare Crown specifications tothose of other manufacturers. But this high level of distortion actually allows for some clipping which is undesirable. Because of this, amaximum average power specification at 0.05% THD is included in each minimum power matrix which represents non-clippedconditions. Although most manufacturers do not give you power specifications at 0.05% THD, we encourage them to provide thesespecifications so you will have a more realistic representation of the way amplifiers should be used in the real world—without a clippedoutput signal.

Many manufacturers publish power specs with a tolerance of ±1 dB or worse. This means their amplifier can deviate more than 20%in output! A 100 watt amplifier would meet their specification if it only produced 79.4 watts. Other manufacturers qualify their specs bysaying they are “typical,” “subject to manufacturing tolerances,” “single channel driven” or that they are specified with “fuses

8

2

Macro-Tech 3600VZ – Minimum Power (Watts)

Stereo/MonoMode

Stereo(both channels

driven)

Bridge-Mono(balanced output)

Parallel-Mono

1

16

4

4

FTC Continuous Average0.1% THD + Noise

(See note 4)

1 kHz 20Hz-20kHz

Maximum Average

Load

(Ohm

s)

AC M

ains

120

VAC,

60

Hz U

nits

1 kHz

0.1% THD+N(See note 1)


20Hz-20kHz

4

2

8

8

2Stereo

(both channelsdriven)


Parallel-Mono

1

16

4

4


1 kHz

4

2

8

100

VAC

Tra

nsfo

rmer

8


driven)


Parallel-Mono

1

16

4

4

4

2

8

2

230

VAC

Tra

nsfo

rmer

885

<680

850

<680

275

1060

2115

2140

895

1780

1785

870

1735

1750

1800

1565

1120

3505

3140

2210

3555

3190

2235

1460

1300

980

2835

2625

1950

2820

2585

1940

1520

1325

965

2800

2515

1900

2910

2565

1935

1035

940

955

1765

1785

1555

1110

3490

3110

2190

3530

3155

2225

1360

1290

970

2825

2600

1940

2810

2550

1925

1495

1300

930

2740

2445

1855

2840

2520

1915

Figure 6.1 Minimum Power Matrix

bypassed.” Each of these statements effectivelyremoves any performance guarantee. In fact, somemanufacturers use these tactics to generate largepower numbers, and they don’t even print a disclaimer.We take a different approach at Crown—our amplifiersare guaranteed to meet or exceed their specificationsfor three years. Further, because our published specsare set below our “in-house” measurements, you canexpect every Crown amplifier to exceed its publishedminimum power specs. We believe you should get whatyou pay for.

Minimum Power Notes:All minimum power specifications are based on 0.5%regulated AC mains with THD of less than 1.0% and anambient room temperature of 70° F (21° C). StandardEIA power (RS-490) is not shown here because it is iden-tical to FTC Continuous Average Power.

1. A 1 kHz sine wave is presented to the amplifier andthe output monitored for nonlinear distortion. The levelis increased until THD reaches 0.1%. At this point,average power per channel is reported.

2. A sine wave is presented to the amplifier over therange from 20 Hz to 20 kHz and the output monitoredfor nonlinear distortion. The level at each frequencyis increased until THD reaches 0.1%. At this point,average power per channel is reported.

3. A 1 kHz sine wave is presented to the amplifier andthe output monitored for nonlinear distortion. The levelis increased until THD reaches 0.05%. At this point,average power per channel is reported.

4. Continuous power in the context of Federal TradeCommission testing is understood to be a minimumof five minutes of operation. Harmonic distortion ismeasured as the RMS sum total and given as a per-centage of the fundamental output voltage. This ap-plies for all wattages greater than 0.25 watts.


Page 32

Maximum Power SpecificationsCrown’s maximum power specifications represent the largest amount of output power you can expect from youramplifier when it is driven to full output under the given conditions. These specifications can be used to preventloudspeaker and hearing damage.

The maximum power matrices include specifications for single cycle and 40 millisecond burst sine waves. Burstsignals act like large transient peaks that are present in common source signals. Loudspeakers can respond to asingle cycle burst, so the single cycle burst specifications should be used to help you protect your loudspeakers. Incontrast, a 40 millisecond burst represents the typical response time of the human ear. Your ear will not respond to theentire dynamic change of a burst that lasts less than 40 milliseconds.

The burst power specifications are provided at 0.05% THD which is a practical low distortion condition. Operating theamplifier at levels higher than 0.05% THD can result in output power levels that are higher than those listed in themaximum power matrices.


driven)


Parallel-Mono

2320

2230

1460

4630

4425

2915

4240

4500

2920

2175

2065

1370

4325

4055

2725

4045

4145

2755

2310

2030

1330

4570

4095

2675

4275

3685

2515

2375

3270

1830

4670

6495

3605

4310

6480

3655

2285

3220

1810

4575

6425

3625

4245

6465

3645

2365

3030

1695

4645

6050

3345

4380

6005

3390


driven)


Parallel-Mono

1610

1745

1235

2930

3355

2420

2880

3380

2425

1490

1530

1155

2715

3020

2285

2680

3035

2275

1695

1485

1095

2935

2940

2160

3030

2690

2035

Macro-Tech 3600VZ – Maximum Power (Watts)

Stereo/MonoMode

40 Millisecond Tone Burst0.05% Distortion + Noise

(See note 2)

Single Cycle Tone Burst0.05% Distortion + Noise

(See note 1)

50 Hz 1 kHzLoad

(Ohm

s)

20 Hz 50 Hz 1 kHz

1610

3140

1760

2930

6140

3460

2880

6125

3485

1490

3170

1770

2715

6270

3510

2680

6260

3500

1695

2890

1615

2935

5765

3215

3240

5770

3230

7 kHz 7 kHz

AC M

ains

120

VAC,

60

Hz U

nits

100

VAC

Tra

nsfo

rmer

2320

1860

1295

4520

3735

2565

4240

3685

2545

1930

1620

1155

3745

3310

2330

3820

3250

2325

2005

1655

1160

4040

3280

2890

3870

3185

2270

2000

1690

1175

3920

3315

2325

3910

3345

2355

1655

1495

1110

3300

2950

2215

3300

2965

2210

1665

1435

1060

3385

2870

2095

2945

2630

1975

(both channelsdriven)


Parallel-Mono

230

VAC

Tra

nsfo

rmer

Stereo

1915

1670

1260

3815

3315

2375

3810

3310

2475

1535

1375

1110

3060

2745

2190

3065

2760

2210

1650

1450

1060

3355

2905

2115

2860

2565

1955

2

4

8

4

8

16

1

2

4

2

4

8

4

8

16

1

2

4

2

4

8

4

8

16

1

2

4

Maximum Power Notes:All maximum power specificationsare based on 0.5% regulated ACmains with THD of less than 1.0%and an ambient room temperatureof 70° F (21° C). Although it is anunusual condition, your amplifiercan function well with AC mainsvoltages up to 10% over the speci-fied line voltage. With overvoltageconditions, your amplifier may becapable of delivering instanta-neous power levels up to 20%greater than the specifications inthe matrix.

1. A single cycle sine wave is pre-sented to the amplifier andmonitored for nonlinear distor-tion. The average power duringthe burst is reported. Loud-speakers must be able to with-stand this level if they are to besafely used with this amplifier.

2. A 40 millisecond sine wave burst(10 percent duty cycle) is pre-sented to the amplifier and moni-tored for nonlinear distortion.Average power during the burstis reported. This power level is ameasurement of the amplifier’smaximum transient power thatcan be perceived by the humanear.

Figure 6.2 Maximum Power Matrix


Page 33

Fig. 6.3 Typical Frequency Response

Fig. 6.4 Typical Damping Factor

Fig. 6.5 Typical Output Impedance

10 100 1 K 10 K 100 K

FREQUENCY (Hz)

+2

+1

0

–1

–2

–3

–4

dB

–5

–6

–7

4 ohm8 ohm1 watt

504.0

126.8

31.8

MILLIOHMS

8.0

2.0

6 dB

20 100 1 K 10 K 20 K

400

200

100

0

600

800

1000

1200

1400

FREQUENCY (Hz)

8 ohm

10 100 1 K 10 K 100 K

FREQUENCY (Hz)

2 ohm


Page 34

Fig. 6.7 Typical Crosstalk

Fig. 6.6 Typical Phase Response(Measured with a TEF® Analyzer)

TECHRON TEF ®

+45˚

0˚

–45˚

100 1 K 10 K 20 K

FREQUENCY (Hz)

TEF®Measurement

TEF®Measurement

100 1 K 10 K 20 K

FREQUENCY (Hz)

dB

TECHRON TEF ®

–60

–66

–72

–78

–84

–96

–90


Page 35

7 AC Power Draw and Thermal DissipationThis section provides detailed information about theamount of power and current drawn from the AC mainsby the Macro-Tech 3600VZ, and the amount of heatproduced under various conditions. The calculationspresented here are intended to provide a very realisticand reliable depiction of the amplifier. The following as-sumptions were made:

• The amplifier’s available channels are loaded, and full,standard 1 kHz power is being delivered.

• Quiescent power draw is 90 watts (an almostnegligible amount for full-power calculations).

• Quiescent heat dissipation equals 105 btu/hr at90 watts.

• Duty cycle of pink noise is 50%.

• Duty cycle of highly compressed rock ‘n’ roll midrangeis 40%.

• Duty cycle of rock ‘n’ roll is 30%.

• Duty cycle of background music is 20%.

• Duty cycle of continuous speech is 10%.

• Duty cycle of infrequent, short-duration paging is 1%.

Here are the equations used to calculate the data pre-sented in Figure 7.1:

AC Mains PowerDraw (watts)

=

Total output power with allchannels driven (watts)

x DutyCycle

Amplifier Efficiency+ Quiescent Power

Draw (watts)

The quiescent power draw of 90 watts is typical, andassumes the cooling fans are not running.

ThermalDissipation

(btu/hr)=

Quiescent PowerDraw (watts)[ ] x 3.415( 1 – Power to Load ) +

or

Total output power with allchannels driven (watts)

ThermalDissipation

(btu/hr)= +

Quiescent PowerDraw (watts)

x DutyCycle

x

Amplifier Efficiency( )x 3.415Amplifier

Inefficiency

The constant 3.415 converts watts to btu/hr. Thermaldissipation in btu is divided by the constant 3.968 toget kcal.

To convert the power draw in watts to current draw inamperes, use the following equation:

Current Draw(amperes)

=

AC Mains PowerDraw (watts)

xAC MainsVoltage

PowerFactor (.83)

The current draw values shown in Figure 7.1 dependon the AC mains voltage (power draw and thermal dis-sipation are typical for any AC power voltage).

*BM=Bridge-Mono, PM=Parallel-Mono

Macro-Tech 3600VZ

8 Ohm Stereo

L O A D

50%

40%

30%

20%

10%

1545

1255

965

675

380

1300

1105

905

705

505

2160

1745

1330

920

505

435

365

295

225

150

2340

1890

1440

990

540

1845

1535

1230

920

615

15.5

12.6

9.6

6.7

3.8

21.6

17.5

13.3

9.2

5.0

23.4

18.9

14.4

9.9

5.4

DutyCycle

AC MainsPowerDraw

(Watts) btu/hr

Current Draw (Amps)

7.8

6.3

4.8

3.4

1.9

10.8

8.8

6.7

4.6

2.5

11.7

9.5

7.2

5.0

2.7

4 Ohm Stereo / 8 Ohm BM / 2 Ohm PM* 2 Ohm Stereo / 4 Ohm BM / 1 Ohm PM*

330

280

230

180

130

kcal/hr

1720

1440

1155

875

590

465

390

310

235

155

100-120 V 220-240 V

Thermal Dissipation

btu/hr

Current Draw (Amps)

kcal/hr100-120 V 220-240 V

Thermal Dissipation

btu/hr

Current Draw (Amps)

kcal/hr100-120 V 220-240 V

Thermal DissipationAC MainsPowerDraw

(Watts)

AC MainsPowerDraw

(Watts)

Fig. 7.1 Power Draw, Current Draw and Thermal Dissipation at Various Duty Cycles


Page 36

8 Accessories8.1 P.I.P. ModulesOne advantage of Macro-Tech amplifiers is the abilityto customize them using P.I.P. (Programmable InputProcessor) and PIP2 modules. Macro-Tech amplifiersare equipped with an edge card connector inside theback panel P.I.P. compartment. The modules installeasily:

FTE


CH-2 INPUT CH-1 INPUT+ – + –

P.I.P.–FTE uses balanced 1:1 transformers to isolate the am-plifier from the input signal. It also includes 12 dB/octave RFIfilters, 18 dB/octave high pass filters, and 6 dB/octave 3 kHzshelving networks for “constant-directivity” horn equalization.Screw terminal plugs are provided for input.

DSPI

AUX

CH-2 CH-1AUDIO IN3

2 1

GND GND

32

1 1

2

IN OUTCROWNBUS

GND OUTIN

3

2

1

MEM#.###

P.I.P.-MEMPUSH PUSH

IQ–P.I.P.–MEM is PIP2-compatible and integrates the ampli-fier into Crown’s patented IQ System®. The IQ System pro-vides computer control of 1 to 2000 amplifiers. For example,each amplifier channel can be monitored and controlled froma personal computer attached to an IQ System. A memorybackup feature enables the IQ–P.I.P.–MEM to remember allconfiguration settings when the power is turned off.

P.I.P.-SMT DSPI

AUX

CH-2 CH-1AUDIO IN3

2 1

GND GND

32

1 1

2

IN OUTCROWNBUS

GND OUTIN

3

2

1

PUSH PUSH

SMT#.###

IQ–P.I.P.–SMT is also PIP2-compatible and includes all thefeatures of the IQ–P.I.P.–MEM plus SmartAmp™ capability.Once the unit has been configured by an IQ System, itsSmartAmp capabilities enable it to function autonomously.We call this distributed intelligence™. The SmartAmp featuresinclude a smooth output limiter for transparent loudspeakerprotection, power supply gates for energy savings, ODEPconservation to protect output devices with precision inputsignal control, interrupt-driven reporting that lets you defineerror conditions, and configurable short circuit detection.

P.I.P.-DSPPUSHPUSH

DSPI

CH-2 CH-1

EXT. POWER INPUT24 VDC / 400 mA

TIP= RING =

IN OUTCROWNBUS

AUDIO OUT

3

2 1

GND CH-2 CH-1AUDIO IN DSP#.###

IQ–P.I.P.–DSP is PIP2-compatible and provides digital sig-nal processing capabilities to your amplifier, replacing theneed for outboard signal processing equipment such asequalizers, crossover networks, signal delays and compres-sors. In addition, the IQ–P.I.P.–DSP includes all the SmartAmpfeatures of the IQ–P.I.P.–SMT to give you access to standardIQ System amplifier functions and autonomous operation.

WARNING: Disconnect power to the amplifier wheninstalling or removing a P.I.P. module.

P.I.P.s carrying the PIP2 logo are configured to use oneor more of the PIP2 enhanced features. These featuresare only available in a PIP2-compatible amplifier. Ofcourse, the exact features used will depend upon thefunction of the PIP2 module. Here are some of the avail-able P.I.P. and PIP2 modules:

AMC


O U T P U T I N P U T3

1 2GND

PUSH

P.I.P.–AMCb unites many features of the P.I.P.-XOV and P.I.P.–CLP. It offers a variable 4th-order Linkwitz-Riley crossoverand an IOC-driven, variable threshold compressor. In addi-tion, it provides “constant-directivity” horn equalization andfilter-assisted B6 vented box equalization. Biamping andtriamping capabilities are provided via XLR connectors.


I N P U T3

1 2GND

PUSH

C H - 2 C H - 1

PUSH

I N P U T

EDCb

P.I.P.–EDCb combines a sophisticated error-driven compres-sor and smooth limiter with a maximum level setting and asubsonic filter for each channel. The compressors have ad-justable attack and release times, and can be set to trackeach other. The compressors activate when a signal wouldotherwise clip the input, an IOC error occurs, or the outputexceeds the selected threshold. The subsonic filters havecorner frequencies of 24, 28, 32 and 36 Hz.

P.I.P.MODULE

BACK PANEL

OF AMPLIFIER

Fig. 8.1 Installing a P.I.P. Module


Page 37

CLP


3

1 2GNDI N P U T I N P U T

C H - 2 C H - 1

PUSH PUSH

P.I.P.–CLP detects and prevents overload. Its compressor isdriven by the amplifier’s built-in IOC error detection circuitry.Unlike typical signal-driven compressors, it only compressesthe signal to prevent overload. It can deliver up to 13 dB ofadditional headroom without being noticeable.

ISO


—WARNING—THIS P.I.P. PROVIDES FULL ISOLATIONFOR ISO-MODIFIED AMPLIFIERS ONLY!

DO NOT CONNECT THE OUTPUT GROUNDLUG TO THE INPUT COMMON OR CHASSISGROUND. REFER TO P.I.P.–ISO OWNER’SMANUAL FOR FURTHER INFORMATION.

+ –CH-2 INPUT

+ –CH-1 INPUT

P.I.P.–ISO is designed especially for 25 to 140 volt distrib-uted systems where UL®-listed isolation is required. Installa-tion requires minor amplifier modifications. With the P.I.P.–ISOinstalled, the amplifier outputs are safely isolated from theinput terminals and the chassis.

0dB.5

1234

56

789111214

1618212430

50∞0dB.5

1234

56

789111214

1618212430

50∞


+ – –ATTENUATION ATTENUATIONATNB

C H - 2 I N P U T C H - 1 I N P U T

+

P.I.P.–ATNB uses balanced 1:1 transformers to isolate theamplifier from the input signal. It also includes 12 dB/octaveRFI filters, variable 18 dB/octave high-pass filters, and 6 dB/octave 3 kHz shelving networks for “constant-directivity” hornequalization. The module also includes a calibrated 21-stepprecision attenuator for each channel. Screw terminal plugsare provided for input.


3

1 2GND

PUSH

XOV

O U T P U T S I N P U T S

+–

TIP

RING

SLEEVEGND

P.I.P.–XOV is a versatile 18 dB/octave mono crossover/filterwith biamping and triamping capabilities


3

1 2GND

PUSH PUSH

FMX

C H - 2 I N P U T S C H - 1 I N P U T S

P.I.P.–FMX facilitates “daisy-chaining” balanced amplifier in-puts. Female to male three-pin XLR connectors are used topassively bridge the inputs.

PA


+– +–LINE MIC

MIC LEVEL

C H - 2 I N P U T S

CH-2 CH-1

REMOTE

+– +–MIC LINE

MIC LEVEL

C H - 1 I N P U T S

P.I.P.–PA adds a switchable balanced low-impedance micinput, a balanced line-level input and a compressor to eachchannel. Remote switching circuitry provides quick and quietfades from mic to line and back.

+– +–OUT

C H - 2

+– +–IN OUT

C H - 1

BEQ


IN

P.I.P.–BEQ is a two-channel module providing equalizationfor BOSE® loudspeakers. For example, the P.I.P.–BEQ canbe used in place of a BOSE 102 controller. Screw terminalplugs provide balanced connections. Each input channelhas an output from the P.I.P. that can be independently con-figured for output with no processing, loudspeaker equaliza-tion or loudspeaker equalization with bass-cut.

RPA

ProgrammableInput Processor + – + –

MIC

LINE

PHAN

TIE

RMT B

RMT A

OUT

INOUT

INRMT C

RMT D

+10 V

A U D I O B U S

CH-2 CH-1

MIC

LINE

PHAN

INPUT D(CH-2)

INPUT C(CH-2)

+ – + –

MIC

LINE

PHAN

MIC

LINE

PHAN

INPUT A(CH-1)

INPUT B(CH-1)LEVEL LEVEL

P.I.P.–RPA adds the features of a 4x2 mixer to your amplifier.Its four inputs accept mic- or line-level input. It offers priorityswitching (“voice-over”) of each input and remote level con-trol with the RPA–RMT. Other features include bus inputs andoutputs, adjustable input sensitivity, phantom power and RFIsuppression. Input isolation transformers are optional.

For more information on these or other P.I.P.s underdevelopment, contact your local dealer or Crown’sTechnical Support Group.


Page 38

8.2 Level Control Security KitThe MA-LOCK security accessory can be used to se-cure your amplifier’s level controls in situations wherethe front panel controls are subject to tampering. TheMA-LOCK security kit includes the necessary hard-

Fig. 8.2 Installing an MA-LOCKLevel Control Shaft Lock

ware to lock the two level controls on the front panel ofany Macro-Tech amplifier. For more information, con-tact your local Crown dealer or Crown’s Technical Sup-port Group.


Page 39

9 ServiceThis unit has very sophisticated circuitry which shouldonly be serviced by a fully trained technician. This isone reason why each unit bears the following label:

CAUTION: To prevent electric shock, do not removecovers. No user serviceable parts inside. Refer ser-vicing to a qualified technician.

9.1 Worldwide ServiceService may be obtained from an authorized servicecenter. (Contact your local Crown/Amcron representa-tive or our office for a list of authorized service cen-ters.) To obtain service, simply present the bill of saleas proof of purchase along with the defective unit to anauthorized service center. They will handle the neces-sary paperwork and repair.

Remember to transport your unit in the original factorypack.

9.2 North American ServiceService may be obtained in one of two ways: from anauthorized service center or from the factory. You maychoose either. It is important that you have your copyof the bill of sale as your proof of purchase.

9.2.1 Service at a North American Service CenterThis method usually saves the most time and effort.Simply present your bill of sale along with the defectiveunit to an authorized service center to obtain service.They will handle the necessary paperwork and repair.Remember to transport the unit in the original factorypack. A list of authorized service centers in your areacan be obtained from our Technical Support Group.

9.2.2 Factory ServiceTo obtain factory service, fill out the service informa-tion page that follows and send it along with your proofof purchase and the defective unit to the Crown fac-tory. For warranty service, we will pay for ground ship-ping both ways in the United States after receivingcopies of the shipping receipts. Shipments should besent “UPS ground.” (If the unit is under warranty, youmay send it C.O.D. for the cost of freight via UPSground.) The factory will return it via UPS ground.Please contact us if other arrangements are required.

your unit’s shipping pack. Do not send the ser-vice information form separately.

2. To ensure the safe transportation of your unit tothe factory, ship it in an original factory packingcontainer. If you don’t have one, call or writeCrown’s Parts Department. With the exceptionof polyurethane or wooden crates, any otherpacking material will not be sufficient to with-stand the stress of shipping. Do not use loose,small size packing materials.

3. Do not ship the unit in any kind of cabinet (woodor metal). Ignoring this warning may result in ex-tensive damage to the unit and the cabinet. Ac-cessories are not needed—do not send theinstruction manual, cables and other hardware.

If you have any questions, please call or write theCrown Technical Support Group.

Always use theoriginal factory packto transport the unit.

Factory Service Shipping Instructions:

1. When sending a Crown product to the factoryfor service, be sure to fill out the service infor-mation form that follows and enclose it inside

Crown Audio DivisionTechnical Support / Factory ServicePlant 2 SW, 1718 W. Mishawaka Rd.,Elkhart, Indiana 46517 U.S.A.

Telephone: 219-294-8200800-342-6939 (North America, Puerto Rico, and Virgin Islands only)

Facsimile: 219-294-8301 (Technical Support)219-294-8124 (Factory Service)

Fax Back: 219-293-9200 (North America only)800-294-4094 (North America only)219-294-8100 (International)

Internet: http://www.crownintl.com

Det

ach

and

sen

d w

ith u

nit.

Crown Factory Service InformationShipping Address: Crown Factory Service, Plant 2 SW, 1718 W. Mishawaka Rd., Elkhart, IN 46517

Phone: 1-800-342-6939 or 1-219-294-8200 Fax: 1-219-294-8124

Owner’s Name: _________________________________________________________________________

Shipping Address: ______________________________________________________________________

Phone Number: _____________________________ Fax Number: _____________________________

Model: ________________________ Serial Number: _____________ Purchase Date: ___________

NATURE OF PROBLEM(Be sure to describe the conditions that existed when the problem occurred and what attempts were made to correct it.)

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

Other equipment in your system: _________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

If warranty has expired, payment will be: Cash/Check VISA MasterCard C.O.D.

Card Number:___________________________ Exp. Date:_______ Signature:____________________________

ENCLOSE THIS PORTION WITH THE UNIT. DO NOT MAIL SEPARATELY.

Model: Macro-Tech 3600VZ

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