Distance alone won't effect pitch if the air is the same temperature and pressure throughout.
If sound waves are traveling at 750mph from point A to point B, they will arrive at the same speed no matter the distance. Only if the points are changing to change the overall speed will pitch change. Sound can travel faster or slower, but the compression rate has to change, and the only way to change that is to move point A or B, or put something inbetween A and B so that the speed changes. But, even if you put water or aluminum between the two points the speed will go back to whatever the speed of sound is in air at a particular pressure/temperature. This is also why those that have attempted to break the sound barrier have been very picky at what temperature/pressure the air is when they fly through it, since the speed of sound is different when it's freezing out, versus when it's during a heat wave. Sound waves don't slow down unless the medium changes. Only the volume of sound changes over distance. http://boards.straightdope.com/sdmb/showthread.php?t=610002 http://www.sengpielaudio.com/calculator-distance.htm The curtains or sound material won't be much of a difference, but stage temperature (from on to off) can be substantial, and a 20 degree F difference can of course change pitch noticeably. -William -----Original Message----- From: Hans Pizka <[email protected]> To: debeeker <[email protected]>; The Horn List <[email protected]> Sent: Sun, May 29, 2011 2:49 pm Subject: Re: [Hornlist] offstage brass Loss of higher harmonics due to less good acoustic environment, yes, as curtains can damp the sound. But how should this affect the intonation ? 440 remains 440, no matter what kind of curtain or deco they use on stage. Higher harmonics have nothing to do with that problem. But the distance effects (lowers) the intonation of a given pitch. We all learned that in school (classic gymnasium, physics classes) which seem to be abandoned in a greater percentage of schools. ############################################# Am 29.05.2011 um 19:47 schrieb Dan Beeker: > Surely there must be more to it than "because of the distance". Does > that mean the listener in the back of the auditorium hears things > flatter than the patron in the front row? Loss of higher harmonics due > to stage curtains etc. might make it sound flatter (total conjecture on > my part). Just curious. Any acoustics people out there have an explanation? > > Dan Beeker > > On 5/29/11 1:00 PM, [email protected] wrote: >> Message: 11 >> Date: Sun, 29 May 2011 16:22:54 +0200 >> From: Hans Pizka<[email protected]> >> Subject: Re: [Hornlist] offstage brass >> To: The Horn List<[email protected]> >> Message-ID:<[email protected]> >> Content-Type: text/plain; CHARSET=US-ASCII >> >> Bob, welcome in Germany, >> >> the off stage brass sounds flat to the player on stage because of the distance. But it is not much. >> So the off stage players adjust the main tuning slide a bit, just a bit >> (1/4" perhaps). >> >> Regards >> >> Hans > > -- > Dan Beeker > > _______________________________________________ > post: [email protected] > unsubscribe or set options at > https://pegasus.memphis.edu/cgi-bin/mailman/options/horn/hpizka%40me.com _______________________________________________ post: [email protected] unsubscribe or set options at https://pegasus.memphis.edu/cgi-bin/mailman/options/horn/valkhorn%40aol.com _______________________________________________ post: [email protected] unsubscribe or set options at https://pegasus.memphis.edu/cgi-bin/mailman/options/horn/archive%40jab.org
