 The Clarinet BBoard
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Author: TianL
Date: 2010-03-11 14:51
My room is a little cold recently and I've found that in this situation (maybe just 5-10 degrees drop compared to the normal 72F), the clarinet has much more resistance and feels completely different. Is this true for all clarinets?
I play a wood one - an R13.
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Author: Paul Aviles
Date: 2010-03-11 15:23
No.
Sounds as if the cold is bringing up a problem such as a rod binding (metal contracts when it's cold) or older key oil becoming gummier and the consesqence being something held open that should be closed or somthing held closed that should be open. Perhaps try a "blow/suction test" before you begin to play just to see if everything is sealing right from the get go.
Once that's clear, check for the "sluggishness."
These are the only things I can think of of the top. I have played well adjusted (GREENLINE) horns in 20 degree (fahrenheit) temps with light drizzle - no problems........other than being miserable.
.................Paul Aviles
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Author: TianL
Date: 2010-03-11 16:59
Thanks Paul for the advice. I'll check these today.
However I'm still confused that the difference can be that big between 60 and 70F though.. could it be the reed that react differently in different temperatures?
Yesterday I was playing upstairs (warmer) and it was fine. Then I moved downstairs (colder) and started to feel this resistance. Then I turned on the heater and once the room's temperature was a bit higher, it was fine again.. so weird.
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Author: Paul Aviles
Date: 2010-03-11 18:30
On the surface, you're right. 60 degrees shouldn't be a problem.......however, I don't like playing a wood horn at anything much less than that because you are blowing 97 degree air down the center of it. As the temperature differential gets greater, you risk cracking.
Perhaps your issue may be as simple as too much condensation getting balled up in a tone hole (or register tube) up high on the horn. But I still think it's the oil thing (definitely something that is going wrong to start, but it is allowed to express itself more freely in the changed temperature).
................Paul Aviles
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Author: Spencer Stromquist
Date: 2010-03-21 00:15
I agree with you TianL.
I feel like my instrument sounds different at cooled temps than warm (R13 Prestige). To help avoid the resistance, I like to warm up the barrel and bell separate from te rest of the horn by placing them each under an arm. While doing this I blow into the rest of the horn with warm air. This generally fixes it for me.
My teacher says that air travels differently through a warm instrument then a cold instrument and a warm instrument is usually more in tune throughout the registers too.
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Author: Tony Pay ★2017
Date: 2010-03-22 14:34
I haven't posted yet on this subject because I haven't been able to track down a proper reference; but Arthur Benade pointed out to me many years ago in conversation that temperature affects the onset of turbulence in a gas as flow rates increase (it occurs at lower flow rates when the temperature is lower).
The presence of sharp edges also encourages turbulence at low flow rates.
You don't want turbulent behaviour because it dissipates energy in a random fashion; the upshot is that wind instruments work better, and play louder without distortion, if tonehole and other edges aren't sharp, and the temperature isn't too low.
I was sure it was in FoMA, but I can't find it. Perhaps it's on that Australian website somewhere....?
Tony
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Author: Paul Aviles
Date: 2010-03-22 15:55
As one asked to play (occassionally) in rather non tradtional playing conditions, I find the intonation issues across the ensemble to be the first and formost challenge. Larger instruments hold larger volumes of air (like a tuba for instance) and the cold air will vibrate slower lowering the pitch MORE so than correspondingly smaller instruments. This scenario forces everyone to attempt a match to the most disadvantaged with varying levels of success. With ALL that going on, it's hard to hear a difference in the volume/resistance (not to mention freezing your fingers off!).
It's certainly nice to hear affirmation that there are yet OTHER reasons not to play outside when it's cold.
.............Paul Aviles
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Author: mrn
Date: 2010-03-29 18:34
Tony wrote:
Quote:
I haven't posted yet on this subject because I haven't been able to track down a proper reference; but Arthur Benade pointed out to me many years ago in conversation that temperature affects the onset of turbulence in a gas as flow rates increase (it occurs at lower flow rates when the temperature is lower).
I have an undergraduate engineering textbook on fluid mechanics (Streeter and Wylie, "Fluid Mechanics," eighth edition), and based on what it says (or my understanding of what it says, anyway--I'm not an expert by any means), what Benade told you makes sense to me. The logic goes like this:
There's a dimensionless quantity called the "Reynolds number" that represents the ratio of inertial forces to viscous forces in a fluid. The Reynolds number gives an indication of whether the flow is laminar or turbulent. For a low Reynolds number, you have laminar (smooth) flow. For a high Reynolds number, you have turbulent flow. Flow becomes turbulent when you reach a certain "critical" Reynolds number for the particular fluid (there's a nice little summary you can look at here: http://www.opticalscientific.com/_pdf/_AppNote/OFS/OFS%20App%20Reynolds%20number.pdf)
The basic formula for the Reynolds number in a tube is:
R = VD/n
where V is the average velocity of the fluid, D is the diameter of the tube, and n (usually written as the Greek letter nu) is the kinematic viscosity of the fluid. (You can also rewrite this formula in terms of flow rate [for continuous flow] by noting that V = Q / A [volumetric flow rate divided by cross-sectional area])
For gases (and air is no exception to this), the kinematic viscosity goes up as the temperature goes up (which is the opposite of what liquids [like the motor oil in your car] do). What this means is that the Reynolds number goes down when the temperature goes up and vice versa. So at higher temperatures, it takes more air flow to reach the critical Reynolds number for the onset of turbulence (and vice versa--at lower temperatures, it takes less flow to reach the critical value).
All that stuff is just basic fluid mechanics, so unless there's something else important at work here that I'm simply not aware of, I'm pretty comfortable with the above explanation of how temperature affects the onset of turbulence. Turbulence is not very well understood, even by physicists, so engineers have to settle for a largely empirical approach to dealing with it (which is what the Reynolds number is).
As far as the sharp edges go, I'm not sure how you explain that quantitatively and I haven't found the answer in my book, but intuitively it would seem to me that a sharp boundary, being a sharp discontinuity from a mathematical point of view, would be more likely to give rise to high-frequency unstable behavior than would be something smoother.
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