I'm a bit short on time now but I seem to remember you can chuck to and from the GenN ugens. Are you sure you need that loop?
Hmm. The documentation agrees with you: "Lookup can either be done using the lookup() function, or by driving the table with an input UGen, typically a Phasor." I tried to drive the Gen5 ugen with an envelope, but that didn't seem to work (or do anything at all). I tried a few other variations on this idea with no result. Maybe this is not what you meant, and what I am doing is completely silly. Noise n => Envelope e => Gen5 curve => dac; [0., 1., 0.] => curve.coefs; 500::ms => e.duration; while (true) { e.keyOn(); 1::second => now; e.keyOff(); 2::second => now; } Let me know what you think. I appreciate the help. Thanks, -Alex