tough sounds to reproduce ???

the tribal drums at the end of the Peter Gabriel song Rythym of the Heat will test many amplifiers and systems - off Peter's 4th album (Security)

as to reproducing musical nuances - yes piano is tough, good way to evaluate cassette tape decks in the old days
percussion can be taxing, and the resonant wood sound of a nice stand up bass can be difficult to do righ ton inferior systems

tom

Stand in the street, right beside a parade that is passing by. Add the sound of twenty or more US Marines marching in perfect cadence and striking their drums in perfect synchronization.

This is so startling that I cannot describe it. The dynamics and overtones went from the extreme highs to well below the pavement and into my bones. I don't think this could even be accurately recorded, much less played back.

sean: if you can find the xrcd2 of "brothers in arms." you'll hear some well-produced thunder. and music.
-kelly

The Female voice singing transitional opera (i.e. a vibratoed note going from soft to loud, etc.). Almost every system I've heard includes an edgy little distortion product that drives me goofy.

The lower octaves of a piano, more than the highs. I like to use piano music as part of my demo of audio gear. If the piano sounds right, the other sounds usually fall in place pretty well.