[chuck-users] continuous random values

Kassen signal.automatique at gmail.com
Tue Sep 28 13:05:54 EDT 2010

> That'd also be a lot less smooth, right? You'd get a mountain range
> instead of a safety scissor edge.

Well, you'd get linear interpolation between random values. That might be
great or crap, depending on your needs. I do think it has to count as "some
sort of random LFO". You could filter the results, you could also wave-shape
them but a wave-shaper that scales like that might be a bit
counter-productive to implement.

> And SubNoise is sample rate
> independent if you take the sample rate into account when you set its
> rate. :D

That does assume a infinite sample-rate. The result of a shred and a
Envelope/step will also be quantised to the sample-clock, but the rounding
error won't carry, like it will with setting SubNoise.

Using a shred, a Step and a LPF will give you all of the advantages of a
Subnoise and a LPF in the smoothness of the curve, without the timing
errors, but it's also a lot more involved than a simple SubNoise.

> This is the 1 Hz weirdness I noticed, by the way. The lines are noise
> generated at 5 Hz, 1.1 Hz, and 1 Hz. You can see the unnaturally long
> plateaus that get way out of hand at 1 Hz.
>  http://skitch.com/alltom/d25q8/subnoise
> But the 5 Hz shape looks pretty nice.
That's strange! Those should indicate the LPF somehow ends up below the
frequency of the subnoise and starts averaging too much. In any case it's
not a bias in the randomness as the plateaus tend to run off towards 0.

What I can say is that at higher frequencies the frequency resolution in
steps per octave of SubNoise will go down and so you will get higher
rounding errors in SubNoise. If that frequency ends up above the frequency
of the LPF we might see something like what you are seeing?

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