Serge Smooth & Stepped Generator SSG

prototype

The SSG is of course the Smooth and Stepped Generator module. It consists of two sub-modules, the top being the Smooth section, the bottom is the Stepped section. The outputs are tied together with a comparator at the CUPL. jack - this gives a HIGH if the smooth output is greater and a LOW if it isn't. *** CAUTION *** HIGH at CUPL is ~ 10VDC, LOW is ~ -10VDC. This is fine for use as a trigger but be careful when using it as a control voltage.... you won't hurt the Serge but if you're using it to control a VCA for example you may destroy your speakers and bring plaster raining down on your head from shattered walls.

Correction: The COUPLER goes HIGH if the STEPPED OUT voltage is greater than SMOOTH OUT. The catalog sheds no light on this but that's what my measurements say.

The Smooth section is a VC lag processor with some interesting additions:
1. Hold input. When this goes high the output no longer tracks the input but is held at the same level that was present when Hold went high.
2. Cycle. This is similar to GATE on the DSG but not the same thing. It is normally not HIGH but LOW (-10V) The Rate knob determines the rate of lag. At zero rotation the rate is low, so that translates to a lot of lag.

The Stepped section is a sample-and-hold, also with interesting additions:
1. A rate knob. This determines how big each step is at the Stepped output. Full rotation=big steps, zero rotation = very tiny steps.
2. Cycle jack. This is also normally LOW (-10V). More on this in another installment.

The stepped section can serve as an extremely high quality sample-and-hold --- MOTM's sample and hold claims a droop rate of about 1mv per second - in other words, if you do a single sample driving a VCO at 1 volt per octave, then hold it and just listen without resampling you should be able to hear a VCO's tone drop perceptibly, without any trouble. An informal test I did measured < 10mv droop in 400 seconds on the SSG. Other listening tests bear this out.

http://www.serge-fans.com/wiz_SSG1.htm