Tutorial 10: Additive Synthesis Basics

In contrary to Subtractive Synthesis, Additive Synthesis is not removing parts of the sound spectrum (by a filter), but adding (by adding harmonics). so some (preferably many) oscillators will be needed, together with VCAs and EGs to control the OSCs’ levels. so, the disadvantage of this kind of synthesis is that it is quite Dsp-consuming. but nevertheless some weird sounds can be obtained which cannot be made otherwise.  if you’ve got ModularIII, a good patch is already stored on your HD: Scope/Devices/ModularIII/Patches/Addi-8.dev. but to get the basic scheme of Additive Synthesis, check out the tutorial below, which is just a cut version of the above-mentioned patch. it’s got just two OSCs, VCAs and EGs but by tweaking some parameters like Partial pitch, EG times, VCA levels, or the EG’s Tmod or Lmod controls you will see how the cat jumps.
If you want some info about the principles of Additive Synthesis, I recommend you to read Gordon Reid’s SOS magazine article.

basic modules: MVC, 2xLinearVCA, 3xMix2, 2xADSRs, esyncAdd2, a polyOut module and

2x sineOSCPartial

(OSC/Sine) these are the vital modules of Additive Synthesis. the Partial controls define the factor by which the basic frequency is multiplied. if you use the textfield and type in integer values (whole numbers), harmonics are produced (1.000= 1st harmonic, 2.000=2nd harmonic, etc.).


-use different factors for the sineOSCPartials
-try different EG settings (also for Tmod1[Velocity] and Tmod2[note])

how to improve this patch (preset list will ne lost):

-use more than just two sinePartial OSCs, try other OSCs
-use multiSegmentEnv or CtrlSeq modules instead of the standard ADSR envelopes

some presets provided.


tut01-basic mono patch
tut02-basic poly patch
tut03-basic Drum OSC patch
tut04-basic seq patch (async)
tut05-PS32 seq remote
tut06-basic seq patch (sync)
tut07-basic CWM morph patch
tut08-Modular as Fx device
tut09-subtractive synthesis basics
tut10-additive synthesis basics
tut11-FM synthesis basics
tut12-AM + RingMod synthesis basics
tut13-Phase modulation basics
tut14-KarplusStrong synthesis basics
tut15-Vector synthesis basics