Tutorial 12: Amplitude & Ring Modulation Synthesis Basics

Amplitude and Ring Modulation Synthesis are similiar as they both are multiplying two audio signals. in Modular, this is done by connecting the outputs of OSC1(modulator) and OSC2 (carrier) either to a VCA module (Amplitude Mod. synthesis) or to a Ringmodulator module (Ring Mod. synthesis). the difference is, that the VCA module converts it’s Mod input to a unipolar signal, while the Ringmodulator does not; it handles both inputs equally. this has an impact on the number of created sidebands (see pics below)
further reading on AM: Gordon Reid’s SOS article in March 2000.

this patch uses 10 modules (VU meter is optional). a MVC, an ADSR, 2x VCA, 2xmultiOSCSyncS, a gate2sync module, LFO, polyOut and:

Ringmodulator

(Effects) this is a simple multiplier module. out = input1 x input2.

tweaks:

use the 2x1 switch to hear the difference between amp & ring mod synthesis.
try different waveforms for Modulator and Carrier, and different coarse + fine tunings. (the LFO module is connected to the OSCs’ Pwm inputs.)

this tutorial patch has some presets.

Carrier: 400Hz, Modulator: 100Hz

fig.1: bipolar Modulator signal (RingMod synthesis)

fig.2: unipolar Modulator signal (AmpMod synthesis)

AMbipolarModulator100Hz
AMunipolarModulator100Hz
tut12AmSynthesis

notes1
notes2
ModularIV
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