grigou

I'm trying to make an ambient patch with some cycle~ with random frequency and tapout~ with big feedback, but I don't understand why the cycle~ volume change so drastically (twice louder) when I choose 200 Hz, 300 Hz, 400 Hz compare to 440 Hz. It seems that, the closer I get from a value like 200, 300, 400, 500, 600, etc. and the bigger the volume is.

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ezdac~

flonum

tapout~

tapin~

cycle~

I'm trying to make an ambient patch with some cycle~ with random frequency and tapout~ with big feedback, but I don't understand why the cycle~ volume change so drastically (twice louder) when I choose  200 Hz, 300 Hz, 400 Hz compare to 440 Hz. It seems that, the closer I get from a value like 200, 300, 400, 500, 600, etc. and the bigger the volume is.

Hello guys !
I'm trying to make an ambient patch with some cycle~ with random frequency and tapout~ with big feedback, but I don't understan

weird-volume-explosion-with-cycle~-and-tapout~

because you have tapout~ set at 10 ms which is 1/100th second, so any frequency that is a multiple of 100 hz will interfere with the delayed version of itself, by reinforcing (adding to) its own amplitude. You will probably find that frequencies halfway between (150, 250 Hz etc) will be attenuated, because the delayed signal will be out of phase with the original, and so the amplitudes will cancel out. This is the principle of comb filtering

Here's an example of constructive/destructive interference using white noise as the source, to alter the spectrum:

So if I want to delay a sine, I will always have this kind of problem.

When I set the tapout~ to 100 ms, now I have the same problem with 210, 220, 230, but not with 209, 219, 229 because 100ms is 1/10th second. So even if I changed the tapout value, I will just move the problem on other frequency values, right ? No solution ?

I have this ambient patch with 2 sine and delay, and I wanted to make a cleaner version.

How can I avoid this delay issue in this case ?

Thank you !
It's much more clear now.
So if I want to delay a sine, I will always have this kind of problem.
When I set the tapout~ to 100 ms, now I have the same problem with 210, 220, 230, but not with 209, 219, 229 because 100ms is 1/10th second. So even if I changed the tapout value, I will just move the problem on other frequency values, right ? No solution ?

I have this ambient patch with 2 sine and delay, and I wanted to make a cleaner version.
How can I avoid this delay issue in this case ?

Nice patch! I'd just reduce the feedback level to less than 0.95, maybe 0.7 or so, so you still get a nice layering without the comb filtering being such a problem (although I don't really see it a s a problem anyway). 

Another more technical way of doing it is to create what's called an allpass structure, where you have two signal paths with identical delays and identical source, but for one of the paths the feedack amplitude is a negative of the other, then add the two signals together (or have each going into their own output channel for a sweet stereo texture)

Nice patch! I'd just reduce the feedback level to less than 0.95, maybe 0.7 or so, so you still get a nice layering without the comb filtering being such a problem (although I don't really see it a s a problem anyway). 
Another more technical way of doing it is to create what's called an allpass structure, where you have two signal paths with identical delays  and identical source, but for one of the paths  the feedack amplitude is a negative of the other, then add the two signals together (or have each going into their own output channel for a sweet stereo texture)

my explanation wasn't exactly correct, you add the inverted signal to feed forward, not feed back, have a look in the allpass subpatch

Weird volume explosion with cycle~ and tapout~