Wow, forget what I said earlier. This sound a lot smarter. Luke Zyla ----- Original Message ----- From: "Steve Haflich" <[email protected]> To: <[email protected]>; "The Horn List" <[email protected]> Cc: "Horn Mailing List New" <[email protected]> Sent: Wednesday, February 10, 2010 9:06 PM Subject: Re: [Hornlist] how much does pitch change with temperature?
> Bob -- This was discussed about a decade ago. Somewhere in my records I > have a more-exhaustive summary, but here is an approximate formula for > speed of sound against temperature > > http://www.sasked.gov.sk.ca/docs/physics/u5b22phy.html > > v = (331 + 0.610t) m/s > > which suggests for each degree C temperature rise a wind becomes > > 1200 log(1 + .610/331) ==> 3.19 cents/degree celsius > > There is a counteracting effect of the instrument flattening due to the > expansion of the tube increasing length, but IIRC my ancient > calculations this effect for brass is only about 1/20 the magnitude of > sound velocity change. > > 7 degree F is a little less than 4 degrees C, so expect a sharpening > around 12 cents. Of course, this ignores the effects of your breath > cooling as it travels down the tube, at a rate that depends on how much > you have been blowing very recently, the difference between the external > temperature and your body temperature, and indeed on the velocity of the > air stream (which depends on dynamics, tessitura, etc. etc.). > _______________________________________________ > post: [email protected] > unsubscribe or set options at > https://pegasus.memphis.edu/cgi-bin/mailman/options/horn/lzyla%40suddenlink.net > _______________________________________________ post: [email protected] unsubscribe or set options at https://pegasus.memphis.edu/cgi-bin/mailman/options/horn/archive%40jab.org
