Dear list, While exploring noise UGens I chanced upon the rather interesting technique of periodically resetting Std.srand() which sets the seed for noise in ChucK, thus resetting the output of the noise UGens; //mind your speakers, ears and neighbours! SubNoise n => dac; .2 => n.gain; while(1) { ((now/2::second)$int)%8 + 2 => n.rate; now%250::ms+ms=>now; 5 => Std.srand; } Interestingly this type of modulation is system-wide so running two files that both try to do this at the same time will result in rather complex sounds. Have fun, Kas.