Pitch: Hot and Cold Flutes

justbarak · Post by **justbarak** » Thu Apr 01, 2004 10:48 am

Just wanting to clear up a discrepancy... Various sites list apparently contradictory information on the affect of temperature on flutes. Many sites state that a cold flute plays flat and a warmed up flute sharpens. Other sites state the opposite occurs. If memory serves me (and it may not), when I played classical flute, my teacher always told me that my flute started out sharp and flattened as it warmed up. Do wooden flutes behave inversely to silver flutes? I would think that as a flute warms up it expands, and getting larger it would flatten. Anyway, just wanting some expert opinions.

Barak

glauber · Post by **glauber** » Thu Apr 01, 2004 11:03 am

I think your teacher was mistaken. A cold instrument plays flat because of the slower speed of sound in the cold air inside. It also plays a little slower for the same reason.

http://hyperphysics.phy-astr.gsu.edu/hb ... uspe3.html

Moisture inside the bore should raise the speed and the pitch too.

mat · Post by **mat** » Thu Apr 01, 2004 11:04 am

They sharpen as they warm......

.....and this is, as I understand, due to the way the air moves rather than the actual instrument expanding.

jim stone · Post by **jim stone** » Thu Apr 01, 2004 11:22 am

mine do it too.

Jayhawk · Post by **Jayhawk** » Thu Apr 01, 2004 12:04 pm

This can be confusing because while flutes do go sharper as they warm up, you have to pull the head out to flatten the pitch to stay in tune (this is provided you initially tune to pitch when the flute is cold).

Eric

glauber · Post by **glauber** » Thu Apr 01, 2004 12:13 pm

As the air warms up, the sound waves travel faster, and you have to make the flute longer (by pulling out) for it to play the same frequency.

g

Post by **Nanohedron** » Thu Apr 01, 2004 2:01 pm

My wooden and polymer sticks sharpen, some more quickly than others. I have no metal flutes. Funny, though; I've heard the same thing about metal Boehm flutes supposedly flattening, too. I could never quite bring myself to give that any credence, and wondered where the idea came from.

peeplj · Post by **peeplj** » Thu Apr 01, 2004 2:47 pm

I own and regularly play a sterling silver Boehm-system flute in addition to my simple system flutes.

Allow me to dispell the myth.

When that flute is cold, it plays not only flat, but very flat. As it warms up, it comes up to pitch. Once it's warm, there is no difference between moderately warm and warm and really warm; it's very pitch stable as long as it's not cold.

Further, the temperature of the headjoint has far more effect than the temperature of the rest of the flute. A flute with a warm body and a cold head plays very flat; a flute with a warm head and a cold body plays reasonably well, but not as well as one that is completely warmed.

Moisture in the bore does nothing for pitch one way or the other, but if it beads up excessively it will cause problems with the tone and responsiveness of the flute. This is why you'll never see me hold a flute exactly level: it needs to be tilted down a bit so the condensate can move down and out of the bore.

--James

justbarak · Post by **justbarak** » Thu Apr 01, 2004 4:42 pm

ahhh... so has little to do with the temperature affecting the instrument, but rathe the temperature affecting the air... Makes sense. Thank you all for your help!!

Barak

DCrom · Post by **DCrom** » Thu Apr 01, 2004 7:06 pm

Straightens things out for me, too. I'd got it in my head that the main effect of cold would be to shrink the flute or whistle, which should RAISE the pitch. Hadn't even stopped to consider the effect of colder air.

Of course, my flute level is still low enough that the effect of my unpracticed embouchure (made worse by frequent layoffs for business trips - I need to get a 3-piece poly flute to haul along) greatly overshadows temperature effects.

But I'd wondered why all my tunable whistles needed the slide all the way in to come to pitch; maybe if I didn't keep the house at 62 F. in winter and would wait a bit before checking tuning I wouldn't have got such a nasty shock.