what are some other things you can do with S/H

[chris_allert]

@godzilla

if you want to hear how it effect a VCO at 200 hz, then you’d need another VCO of at least 200 hz so that it can sample each period of the waveform?

the nyquist frequency ( http://en.wikipedia.org/wiki/Nyquist_frequency ) is the minimum frequency you can sample at to accurately encode the maximum frequency in your signal. (read the link for a more accurate description) in short, the nyquist frequency is twice the frequency you want to sample.

cds are sampled at 44100 hz so they can accurately encode frequencies up to 22050 hz. likewise, if you are sampling at 200 hz, the maximum frequency you’ll be able to sample is 100 hz. and you’ll hear a lot of artifacts created by all the rough edges in your signal because you’re not filtering them out. it’s the same phenomena as the aliasing you get when you digitally sample at too low a frequency, and why digital to analog converters have low-pass filters in them.

if you sample a 200hz vco at exactly 200hz, in theory you’ll get a straight line (silence) since you’ll always be hitting the waveform in the same place. sample a 100hz vco, and you’ll get a square wave. sample a 50hz vco and you’ll get a very rough “stair step” approximation of the waveform you’re sampling.

personally i think sample/hold applications sound a lot more interesting when used to control other modules, and when the control signals are in the sub-audio frequency range, since that way you can really hear the interactions between the sampling waveform and the sampled waveform. but it’s a matter of taste.

[asd]

@Duke Foog

nevermind i’m a goof. i just saw it. but i still don’t understand how you can control the 102’s frequency and 101’s cutoff by going into the attenuators. or do you mean the attenuators on the mixer?

Sorry, I should’ve been clearer about this. In addition to all of the above patching (which would just have the 101 producing the same frequency wave and the s/h circuit sampling at the same speed), I used the lfo’s from the 251 and 102 to modulate the cutoff and frequency. Here’s the specifics:

102-
patching - “lfo out” to 251’s attn 1 “in” - attn 1 “out” to 101 “cutoff”
knobs - rate at .1 and set to triangle wave

251-
patching - “/” out to attn 2 “in” - attn 2 “out” to 102 “frequency”
knobs - rate at .2

@godzilla

what does it sound like?

Sampling the cutoff and using the 2 lfo’s sounds like a really dirty, edgy version of the 101 with the frequency going up and down in different ways depending on how the 2 lfo’s were interacting. higher sampling rate created a clearer sound.

Sampling a guitar sounds like a dirty, messed up version of a guitar. It created a different texture that you may or may not be able to find a use for depending on your tastes.

@chris allert

personally i think sample/hold applications sound a lot more interesting when used to control other modules, and when the control signals are in the sub-audio frequency range, since that way you can really hear the interactions between the sampling waveform and the sampled waveform. but it’s a matter of taste.

After playing around with sampling the audio a little bit I’m going to agree, but it’s always interesting to find out new ways to use things to get different sounds. Stuff like this always teaches me more about the technical end of my equipment so it’s good in that way too.