<HTML>At 10:55 AM -0700 4/30/03, Delwin D. Fandrich wrote:<B= R> >A variable time lag depending on the level of play and on pitch? What ca= uses >the variations? Mainly the volume (cubic space: length and bore of the tube) of the air column  being activated. Air is far more compressible than steel, <= BR> and thus takes longer to give itself to a standing wave. Think high-C on a trumpet vs. the bottom note on a Wagnerian tuba. Bill Ballard RPT NH Chapter, P.T.G. </BLOCKQUOTE> As a former back-row play= er (bass trombone), might I suggest that players are also conditioned to ant= icipate justsoslightly because of the difference in distance between the tro= mbone section and, say, the concertmaster, principal cello, flute and oboe--= from the perspective of the conductor.  We got tired of always "playing= behind the beat," and instead played just slightly ahead.......problem solv= ed. Stan Ryberg Barrington IL Associate Member mailto:jstan40@aol.com</HTML>