(Phil) The instrument does get a tiny bit shorter (about 2 mm at -50°C) but the overwhelming effect is the reduction in the speed of sound as the temperature goes down. Since there is a standing wave in the instrument the lower speed causes it to take longer to go down and up the instrument, thus lowering the frequency and therefore the pitch. In effect the instrument becomes longer as far as the standing wave sees it. Of course the player's breath warms it up quite a bit, about halfway beteen ambient and body temperature. Even allowing for this (which I didn't in my original posting), the adjustment is about one inch on the tuning slide for 20 degrees and this is just a bit more than is usually available. So if you're playing outside at 0°C all you could do would be to play "short", as they say. Fortunately I don't do marching bands or Sally Army stuff.
(Darren) That's correct. The whole instrument would be flat and it wouldn't sound wrong but any other instrument accompanying it would have to tune down a bit. Rather difficult with a piano. One way round it would be to have a small bleed of a lighter gas into the air the organ uses. You could use hydrogen, helium, neon, methane, ammonia or hydrogen fluoride. Perhaps I should patent this lunacy.
Wouldn't some of those risk producing the Amazing Exploding Organ? That puts me in mind of the Large Hot Pipe Organ which produces sound by exploding a propane/air mix in its pipes.
(Darren) It's blown itself to pieces and taken the website with it. I drew a blank with your link, alas. Helium would be safe enough and it's much cheaper than it used to be. It would be amusing to use sulphur hexafluoride, totally inert and non-toxic. It would lower the pitch by over an octave. I think I'd better shut up now.
My curiosity is partially because I'm playing carols at the village Christmas tree tomorrow evening with the local brass band. Getting 40 or so of us in tune may be interesting if we get a cold evening.
(Phil) If all the brass is out of tune by the same amount it won't matter. I suspect there will be enough left on the tuning slide to accomodate an average cold evening.
[Darren] I'm currently reviving my interest in playing B-flat cornet, having not really played it for nearly 3 years. [Rosie] That was what I thought. I might have to get a bit of practice in tonight, and give the old horn a good clean.
(Phil) I hope your lip won't have gone. I wouldn't dare go three days without blowing a few raspberrires down my nine-foot tube. Brass is a treadmill; constant practice just to stand still.
[Rosie] I was jolly chuffed with my performance as 2nd Cornet. Good news was that my part had nothing above more than an octave above Middle C, so my lip survived with no problems. They've now gone and asked me to join them on Sunday morning to play at various points around the village, traditionally accompanied by hip-flasks. Mr Phil has given permissions, so it looks like I might end up signing up to join permanently in the New Year.
(Phil) Shouldn't be too bad. One is expected to get that note on the 'bone (not too often) but the worst thing about it is reading it, being all in bass clef. The rule is that if it's in the stratosphere and on a space it's a C, otherwise it's a B (usually Bb). If it's a D the composer/arranger is not a trombone player. These high notes are far better played by trumpets and cornets anyway. Power to your embouchure. :-)
(Darren) Although leger lines are part and parcel of trombone playing (especially 1st and 2nd trombones) I'm very glad they don't go into Tenor Clef which to me would make it unreadable instead of merely difficult. Treble Clef is never used because most 'bonists can't read that either unless like me they're also piano players.
[Raak] It happens often enough for you to realise that you shouldn't get caught out by it, if that makes any sense. Depends on what key you're in, you see...