interesting question, unfortunatley i don't know the answer but i am also interested!

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serpmusic.com

I've done calculations for delays, but never for compression. With compression you've just gotta go with what feels right, it's not a precise science.

That being said, you'll probably want 1/8 notes so that you've got a more danceable bassline, with the offbeat complimenting the kick drum.

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http://www.aponaut.com

If you have good monitors, you can hear the compression. You need to set the release so that it releases before the next beat comes in. Mix engineers don't calculate this but listen to the results. It takes time and practice before you can get it right.

ok i got right ansver!

my purpose was make pumping effect like "a la prytz"...

so then 1/4 was correct

so when tempo is 125 tou can calculate that theres 11.48 beaats in 25 sec.

11.48x 41.81 (wich is stabile)= 479,9788 = 480

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-keep it hard-

The best method for finding the release is to throw all the math crap out the window. If you go by some black art algorithm, you're going to end up with a funky noise when the compressor releases. Instead, set the release to about 500ms. Then, decrease the time until you can hear the processing is noticeable. Then increase it slowly until it isn't.