[bug?] noise and downsampled poly~

jvkr's icon

The range of values that noise~ produces changes with downsampling.

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jvkr's icon

When trying to fix it with a pong~, it appears the problem goes deeper.
This is with max 6.0.3 on Lion.

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Roman Thilenius's icon

isnt that because they changed how noise~ generates its ooutput with v.5?
if the new alg would somehow avoid that two or more peaks follow each other that would explain what you see.

Peter McCulloch's icon

This is caused by the new resampling filters. There's some overshoot in the interpolation. When you turn it off, this goes away. (they're on by default)

It looks like there's some sort of sinc function at the discontinuity on the phasor. It's pretty cool to watch. Also, check out the spectroscope for interpolation on or off. You can really see the resampling filters blocking everything above the new Nyquist rate.

Max Patch
Copy patch and select New From Clipboard in Max.

If you look at the scope~ on the left you'll see a smoothed noise function. Not a bug, just not maybe what you expected.

And the poly vox:
Max Patch
Copy patch and select New From Clipboard in Max.

`

Peter McCulloch's icon

Forgot to include...

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jvkr's icon

That makes perfect sense. I have seen the resampling mentioned, but forgot about it. Thanks.