7/29/2019 Computermusic Tutorials AdvancedFX4 http://slidepdf.com/reader/full/computermusic-tutorials-advancedfx4 1/4 make music now Modulation FX masterclass 048| COMPUTER MUSIC FEBRUARY 2006 TUTOR IAL Modulation Discover what modulation’s all about and how you can incorporate its family of effects into your tracks T his month in our Advanced FX series we’re looking at the class of processing tools and techniques known as modulation effects. This is a bit of a strange one, as unlike reverb and delay effects (all the respective types of which are merely variations on a theme), modulation effects are connected in the sense that they all share a common element – namely, they involve some type of modulation. In other ways, many modulation effects can be quite different. So what’s it all about? Well, modulation, in production terms, simply means using one parameter to control another. In practice, with effects, this almost always involves using a Low Frequency Oscillator to exercise said control, although there are some exceptions. But never mind that for now: if ‘modulation effects’ is simply an umbrella term for a variety of different effect types, we’d better have a go at explaining the main ones… cm On the DVD TUTORIAL FILES The audio files used in the walkthrough on p51 can be found in the Tutorial Files folder on the DVD Modulation types CHORUS Legend has it that chorus was invented by Roland in their Jazz Chorus amplifier. The amp sent a dry signal to one amp and speaker, and the same signal was delayed, modulated and sent to another amplifier and speaker within the same cabinet. This is a good explanation of how chorus works – except that instead of feeding two amps, in a modern plug-in the two signals are combined. The second, modulated signal is not only delayed but also pitchshifted slightly, and an LFO controls the modulation of this pitch and thus the character of the effect. Originally intended to simulate the sound of more than one instrument or vocal part, it soon became apparent that it didn’t, and now chorus is simply used as a creative effect. 7Chorus sounds particularly good on pads and guitar riffs PHASING AND FLANGING The terms phasing and flanging have become confusing over the years, largely because the effect we now call flanging was originally called phasing and the effect we now call phasing is rather similar to flanging. The concept of flanging stems from running two synced tape machines (playing the same signal) and manually slowing one with your finger (and then the other). This created a distinctive whooshing sound. Phasing, on the other hand, is similar, but without the fast changes and whooshes. In both cases, as the two signals move closer (phasing) and further (flanging) apart, some interesting frequency cancellations occur as similar or identical frequencies cancel each other out or build on each other. Dynamic variation to these effects can be produced with an LFO controlling the timing and intensity of the modulation, and in the case of flanging, the effect is intensified by feeding some of the wet signal back into the equation. RING MODULATION Ring modulators are tricky to understand, but very simple to use, fortunately. The basic concept is that two signals are brought together and then the sum and difference of the frequencies of both are generated, while the rest of the signal is removed. So if you had a 500Hz sine wave and an 800Hz sine wave, the output would feature tones at both 1300Hz and 300Hz. Of course, real sounds are much more complicated than that, and it would make your head explode to figure out on paper what this actually produces when two complex signals are combined. To summarise the effect, it can sound an awful lot like the Daleks talking. VIBRATO/TREMOLO/PANNER If you reduce the delay time in modulation effects down to 10ms or less, it's difficult to distinguish between the original and delayed signal, and so you can then get on with the business of creating tremolo and vibrato. Variations on a theme, the basic difference is that the latter involves modulating the pitch of a sound, the former the volume. Things get a bit more interesting when you offset the left and right channels of a tremolo so that as one peaks the other’s at its lowest point, thus generating either synced or LFO- driven panning, the use of which should be self- explanatory! 7Tremolo is an endlessly useful volume-related effect ADVANCED EFFECTS PART 4 CMU96.t_fx 048 CMU96.t_fx 048 22/12/05 11:24:27 am 22/12/05 11:24:27 am
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
ModulationDiscover what modulation’s all about and how you can
incorporate its family of effects into your tracks
This month in our Advanced FX
series we’re looking at the class
of processing tools and
techniques known as modulation
effects. This is a bit of a strange one, as
unlike reverb and delay effects (all the
respective types of which are merely
variations on a theme), modulation
effects are connected in the sense that
they all share a common element –
namely, they involve some type of
modulation. In other ways, many
modulation effects can be quite
different. So what’s it all about?
Well, modulation, in production
terms, simply means using one
parameter to control another. In
practice, with effects, this almost always
involves using a Low Frequency
Oscillator to exercise said control,
although there are some exceptions.
But never mind that for now: if
‘modulation effects’ is simply an
umbrella term for a variety of different
effect types, we’d better have a go at
explaining the main ones… cm
On the DVDTUTORIAL FILES
The audio files used in the walkthrough on p51 can be found in the Tutorial Files folder on the DVD
Modulation typesCHORUS
Legend has it that chorus was inventedby Roland in their Jazz Chorus amplifier.
The amp sent a dry signal to one ampand speaker, and the same signal wasdelayed, modulated and sent to another amplifier and speaker within the samecabinet. This is a good explanation of how chorus works – except that insteadof feeding two amps, in a modern plug-in
the two signals are combined. Thesecond, modulated signal is not only delayed but also pitchshifted slightly, andan LFO controls the modulation of thispitch and thus the character of theeffect. Originally intended to simulate
the sound of more than one instrumentor vocal part, it soon became apparent
that it didn’t, andnow chorus issimply used as acreative effect.
7 Chorus sounds
particularly good on
pads and guitar riffs
PHASING AND FLANGING
The terms phasing and flanging havebecome confusing over the years, largely because the effect we now call flanging
was originally called phasing and theeffect we now call phasing is rather similar to flanging. The concept of
flanging stems from running two synced tape machines (playing the same signal)and manually slowing one with your
finger (and then the other). This created adistinctive whooshing sound. Phasing, on
the other hand, is similar, but without the fast changes and whooshes. In bothcases, as the two signals move closer (phasing) and further (flanging) apart,some interesting frequency cancellationsoccur as similar or identical frequenciescancel each other out or build on eachother. Dynamic variation to these effectscan be produced with an LFO controlling
the timing and intensity of themodulation, and in the case of flanging,
the effect is intensified by feeding someof the wet signal back into the equation.
RING MODULATION
Ring modulators are tricky to understand,but very simple to use, fortunately. Thebasic concept is that two signals arebrought together and then the sum anddifference of the frequencies of both aregenerated, while the rest of the signal isremoved. So if you had a 500Hz sine
wave and an 800Hz sine wave, theoutput would feature tones at both1300Hz and 300Hz. Of course, realsounds are much more complicated
than that, and it would make your head explode to figureout on paper what thisactually produces when twocomplex signals arecombined. To summarise theeffect, it can sound an awfullot like the Daleks talking.
VIBRATO/TREMOLO/PANNER
If you reduce the delay time inmodulation effects down to 10ms or less,it's difficult to distinguish between theoriginal and delayed signal, and so youcan then get on with the business of creating tremolo and vibrato. Variationson a theme, the basic difference is that
the latter involves modulating the pitch of a sound, the former the volume. Thingsget a bit more interesting when you offset
the left and right channels of a tremoloso that as one peaks the other’s at itslowest point, thusgenerating either synced or LFO-driven panning, theuse of whichshould be self-explanatory!
7 Tremolo is an
endlessly useful
volume-related effect
ADVANCEDEFFECTS
PART 4
CMU96.t_fx 048CMU96.t_fx 048 22/12/05 11:24:27 am22/12/05 11:24:27 am
Use them on… There are no hard and fast rules as to what you can and can’t use modulation effects on, buthere are some suggestions based on the most popular uses.
CHORUS
Backing vocals, pads, backingguitars, strings
VIBRATO, TREMOLO
Pads, vocals,percussion, loops
RING MODULATION
Special vocal effects, drumloops, edits
PHASING AND FLANGING
Guitars, lead synths, drumloops, edits
1Some chorus effects offer multiple delays for an
even thicker sound
3If your modulation
effects offer tempo
sync, use it!
3 Try a straight
pitchshifter to avoid
obvious LFO cycling
CMU96.t_fx 050CMU96.t_fx 050 22/12/05 11:24:38 am22/12/05 11:24:38 am