gstopp at gstopp at
Thu Oct 10 23:44:26 CEST 1996

     Here's an example of a basic full-featured system:
     VCO 1 Fine Tune
     VCO 1 Coarse Tune
     VCO 1 Initial Pulse Width
     VCO 1 Modulation Depth
     VCO 2 Fine Tune
     VCO 2 Coarse Tune
     VCO 2 Initial Pulse Width
     VCO 2 Modulation Depth
     VCF Cutoff Frequency
     VCF Resonance
     VCF (+) Modulation Depth
     VCF (-) Modulation Depth
     ADSR 1 Attack
     ADSR 1 Decay
     ADSR 1 Sustain
     ADSR 1 Release
     ADSR 2 Attack
     ADSR 2 Decay
     ADSR 2 Sustain
     ADSR 2 Release
     VCA 1 Initial Gain
     VCA 1 Modulation Depth
     VCA 2 Initial Gain
     VCA 2 Modulation Depth
     LFO Rate
     Glide (Portamento) Amount
     Input/Output Jacks:
     VCO 1 Exponential FM input (4)
     VCO 1 Linear FM DC input
     VCO 1 Linear FM AC input
     VCO 1 PWM input
     VCO 1 Sync input
     VCO 1 Sawtooth output
     VCO 1 Pulse output
     VCO 2 Exponential FM input (4)
     VCO 2 Linear FM DC input
     VCO 2 Linear FM AC input
     VCO 2 PWM input
     VCO 2 Sync input
     VCO 2 Sawtooth output
     VCO 2 Pulse output
     VCF Exponential FM input (2)
     VCF Audio input (4)
     VCF (+) Modulation input
     VCF (-) Modulation input
     VCF Lowpass output
     VCF Bandpass output
     VCF Highpass output
     VCF Notch output
     ADSR 1 Gate input
     ADSR 1 Envelope output
     ADSR 2 Gate input
     ADSR 2 Envelope output
     LFO Triangle output
     LFO Square output
     White Noise output
     Pink Noise output
     Random Noise output
     External CV input (or multiple to send to VCO's etc.)
     External Gate input (or multiple to send to EG's etc.)
     VCA 1 (+) signal input
     VCA 1 (-) signal input
     VCA 1 Control input (2)
     VCA 1 output
     VCA 2 (+) signal input
     VCA 2 (-) signal input
     VCA 2 Control input (2)
     VCA 2 output
     The Coarse Tune pots on the VCO could be octave rotary switches if 
     desired. You may even be able to get rid of the Fine Tune pots if you 
     use 10-turn or 20-turn panel pots for the Coarse Tune.
     As for any additional controls - there's two primary approaches to 
     modulation routing in modular synthesizers - I'll call them the "Moog 
     approach" and the "Emu approach".
     The Moog approach is to put all the minimum pots on each module, and 
     dealing with modulation depths and signal strengths (really the same 
     thing in a true modular) by the use of attenuators and mixers on 
     seperate panels.
     The Emu approach is to provide all of the minimum pots on each module, 
     and then provide additional pots on each module as input level 
     controls for the audio as well as the CV inputs. The modules become 
     more complex and costly, but more self-contained.
     Whatever you want to do. feel free. The Emu approach will probably 
     cost more and take up more panel space, and lots of pots will go 
     un-used most of the time, but it sure is easy to make patches.
     Regarding the CV and Gate inputs - the VCO and VCF CV inputs are 
     exponential at 1 volt per octave. The Gate input is a positive 
     V-trigger, with the threshold adjustable on a trimpot on each ADSR to 
     be anywhere between ground and +15 volts. There is no pulse trigger 
     input - the ADSR's require only a Gate input (positive voltage as long 
     as a key is held down).
     Hope this helps,
     - Gene
     gstopp at

______________________________ Reply Separator _________________________________
Subject: ASM-1
Author:  Bert.Schiettecatte at at ccrelayout
Date:    10/10/96 1:54 PM

can anyone tell me where I can get full building information for 
this beast ?
Generally, what would be <very> intresting inputs/outputs/switches/pots 
on a modular ?
thanks in advance!

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