So, if there's no such thing as "perfect" perhaps we should lobby for its removal from Webster's. Of course, that would probably lead to total chaos in the dictionary industry, inasmuch as all words are human invention. There is no such thing as a "Tiger". It's just a noise that we make to refer to a big stripey cat. That said, here's a decent wikipedia entry that discusses perfect pitch / absolute pitch. Perhaps I missed an earlier link. If so, apologies for the duplication. <a href="http://en.wikipedia.org/wiki/Absolute_pitch">http://en.wikipedia.org/wiki/Absolute_pitch</a> BTW, I have seen two classroom instructors correctly state and agree that an interval was off by .1 (that's point one) cent. Their observation was aural, verified by a highly-respected (by most) ETD. Paul Bruesch Stillwater, MN