did some tests on sample playback in max/msp, sharing because i thought i understood this stuff but just how bad it can sound surprised me. so: based on some tests oskari tamelin (of buzz fame) did, you take a sample of a 15khz sine and play a c major scale up and a c major scale down with it. dog music, bat jams. here's a synthesised example of what it'd sound like if playing back samples at different pitches didn't introduce problems. these are on the edge of my hearing, the highest i don't hear at all: