Sample-Hold is a really neat way of producing random or pseudo-random control voltages. It’s a good way of introducing an unpredictable filter cut-off frequency or audio level into a synthesizer “patch”.
How our sample-hold structure works.
The idea is to take a random (white noise) audio signal (no reason why you can’t use any other form of audio or CV though, but this won’t be really random), and to sample it at regular intervals by using a clock oscillator.
1) The sample/hold module has two inputs, Audio, which is the signal we are sampling, and Hold which is a pulse which tells the module when to sample the incoming audio signal, once the audio has been sampled this voltage will then be “held” until the next sample pulse is received.
2) There is a Many ->1 switch on the audio input which allows you to select from an external audio voltage, and an internal white noise generator.
You could use a standard oscillator set to white noise, or Elena’s ED Noise Gen for the noise source.
3) The Clock Source Switch allows you to select between an external trigger pulse, such as the keyboard, and the internal clock oscillator.
4) Adding the ED Glider module allows us to smooth out the output of the Sample Hold module to produce a glide effect on the resulting CV.
5) The Hold Clock uses a TD LFO B module preset to 25% pulse waveform to generate the regular train of sampling clock pulses- you could also use a standard oscillator set to pulse, with a narrow pulse width though.
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