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Make Noise modDemix User Manual

Page 6

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Using same patch as above, add a negative offset to the Cycling CH. 1 of MATHS, by adjusting CH. 2 panel

control to full CCW. Observe Balanced Modulation. Observe the low amount of Carrier Feed-Thorough.

Depending upon the Negative Offset added, the Carrier all but vanishes, making the resulting Sidebands

more audible. This is the sound most commonly associated with Ring Modulation. Experiment with different

amounts of negative offset, which could said to control the Depth of the Ring Modulation. Also experiment

with different Carrier Strengths and observe the resulting timbre and amplitude changes.

Return the CH. 2 panel control to 50% (NULL). Set CH. 4 of MATHS for a slow Rise and Fall, and set the

corresponding attenuvertor to about 10 o’ Clock. Initiate the cycling behavior at CH. 4. Observe voltage

control over Ring Modulation Depth. Experiment with combinations of DC Offsets (MATHS CH. 2), triggered

or Cycling Offsets (CH. 4 MATHS) added to the Carrier (MATHS CH. 1). Patch a sequencer from Pressure

Points to CH. 3 MATHS and add that to the Carrier (as generated by CH. 1 MATHS). Experiment.

Patch Ideas:

VCA

Patch signal to be processed (audio or control) to Signal IN. Patch uni-polar control signal such as Envelope,

LFO, Pressure Points CV or gates, to the corresponding Carrier/ CV IN. Take output from Signal OUT. Use

Strength to set the level of the resulting signal. If the Carrier/ CV Signal is oscillating at audio rate, you will

achieve. Amplitude Modulation. Like Ring-Modulation, AM produces audible sidebands. The main difference

is that the Carrier signal is not suppressed, so along with those sidebands, you hear the Carrier. Musically

speaking, this sound is quite useful when a complex timbre is desired, but not at the loss of a strong root

note.

Balanced Modulation, aka “Ring Modulation,” aka Frequency Mixing

Patch audio signal to be processed to Signal IN. This will be the Program. The Carrier signal should be a

bi-polar Audio Rate Signal such as a VCO (so it needs to swing from positive to negative). The resulting

signal, at Signal OUT, will be the result of the Signal IN having both amplitude and phase directly related to

that of the Carrier/ CV IN. To achieve single or double sideband, the balanced modulator is followed by filters

tuned so as to eliminate all but one or two sidebands. Obviously, this is not entirely possible within the

current synthesizer system, since it requires filters designed exclusively for the job, still many interesting

timbres may be heard by using two band pass filters in parallel after the modDemix, for “Stereo-Quasi-

Double-Sideband.” Modulating the filter cutoff will animate the sidebands.

Control Signal Multiplication or Voltage Controlled Polarization

Same as Balanced Modulator patch, only both the Signal IN and Carrier IN are both Control Signals as

opposed to Audio Signals. Use the signal patched to Carrier/ CV IN to multiply the Signal patched to Signal

IN. Take output from Signal OUT. Remember the “Thru-Zero VCA” concept when trying to understand how to

use this patch.

Voltage Controlled Mixer
Use the VCA patch, apply control signals such as the CV outs from Pressure Points to the Carrier/CV Ins of both

channels. Take output from SUM out. Create larger mixes by chaining several ModDemix and/or Optomix together.

To do this patch the SUM out from one into the Aux. IN on the next one in the chain, and so on, to create 2, 4, 6, 8

channel mixes.

Simple Mixer with Chaining

Patch two signals to be mixed to Ch1 and Ch2 Signal INputs. Adjust relative amplitudes with Ch1 and Ch2

STRENGTH controls. Chain additional elements (such as an Optomix or another modDemix) via the AUX

input. Mixed signal will appear at SUM OUTput.