 The Clarinet BBoard
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Author: skygardener
Date: 2008-03-15 03:03
Just thinking about pitch and intonation and being in-tune or not and this question came to me. What is STP (standard temperature and pressure) for clarinets? What is the environment/temperature/humidity level, etc. that a clarinet will play best in-tune at??
By the same token, are the instruments of one company designed to play better at one temperature than another company's instruments?
Post Edited (2008-03-16 08:27)
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Author: NorbertTheParrot
Date: 2008-03-15 14:52
I'm not at all sure the pressure makes any difference. The speed of sound in an (ideal) gas is proportional to the square root of the absolute temperature, but is independent of pressure. Around room temperature, the speed of sound varies by about 0.17% per degree Celsius.
As for the effect of temperature, surely we need to consider both the ambient temperature, and the temperature of the air being blown into the instrument. Tuning a clarinet using an "artificial player" blowing air at ambient temperature would be likely to produce an instrument that played rather sharp when played by a person.
What goes for temperature goes also for humidity. The air being blown into a clarinet will be saturated with moisture; the ambient usually won't be.
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Author: rtmyth
Date: 2008-03-15 16:58
Ambient temperature range of about 68F to 72F for good tuning. From around 80F upward, the instrument is uncontrolably out of tune, like in Texas, outdoors, in the summer.
richard smith
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Author: tictactux ★2017
Date: 2008-03-15 17:38
> I'm not at all sure the pressure makes any difference. The speed of sound
> in an (ideal) gas is proportional to the square root of the absolute
> temperature, but is independent of pressure.
That may very well be, but when I play at altitude, I can feel the different restistance in reed and setup as well as the relative stuffiness of the usual suspect notes.
I did not notice any changes in tuning, but I have no absolute pitch, and I didn't care to bring my tuner with me just to noodle the pieces for the next gig.
(When I burp during playing, my pitch drops. Which probably just demonstrates that beer and soda don't contain ideal gases) ![[tongue]](http://test.woodwind.org/clarinet/BBoard/smileys/smilie6.gif)
--
Ben
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Author: NorbertTheParrot
Date: 2008-03-15 18:09
Ben - altitude does indeed cause increased resistance. Not surprising. Taking it to the limit: no air, no reed motion. Altitude does not affect pitch.
As for the burping, this is nothing to do with idealness or otherwise of the gases. The carbon dioxide in the beer bubbles is denser than air, and causes the speed of sound to drop. The speed of sound in a gas is inversely proportional to the square root of the molecular mass of the gas.
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Author: Neil
Date: 2008-03-15 19:16
OK, how many of you thought this thread was about Andy Granatelli and oiling keys?
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Author: tictactux ★2017
Date: 2008-03-15 20:15
Neil wrote:
> OK, how many of you thought this thread was about Andy
> Granatelli and oiling keys?
<raises hand>
Well, not Granatelli, but certainly oiling keys.
(btw is this an urban legend or do clarinetists, when appearing on TV, mask their instruments' logos with black tape?)
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Ben
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Author: hans
Date: 2008-03-15 21:40
Neil,
Re: "OK, how many of you thought this thread was about Andy Granatelli and oiling keys?"... the STP in the thread's subject line made the oil additive come to mind (but not Andy). I wondered how that thick goo (supposedly an oil viscosity index improver) could possibly be useful in oiling a clarinet.
Hans
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Author: Don Berger
Date: 2008-03-16 01:04
Rite chuare, Hans. Trying to recall my brief experience in lube oil mfgr'g, a VI Improver should help [very slightly] the flowability at low temps [where cls should not be played] and not thin out at higher temps [such as in an I C engine !!] so as Shak said, "much ado about next to nothing", for we'uns. I go with NTP's conclusions re: the cl's internal air pressure and composition [CO2 from Global Warning isn't that bad YET], BUT playing bari sax at 9300 ft, Silverton CO, left me breathless and gasping !! Never agin, Don
Thanx, Mark, Don
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Author: C2thew
Date: 2008-03-16 07:19
exactly what i was thinking! "boost your clarinets performance by enhancing the wood with STP motor oil............" and then pass out from the fumes.
Our inventions are wont to be pretty toys, which distract our attention from serious things. they are but improved means to an unimproved end, an end which was already but too easy to arrive as railroads lead to Boston to New York
-Walden; Henry Thoreau
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Author: BobD
Date: 2008-03-16 19:34
"Altitude does not affect pitch"
I guess I'm not so sure of that as you are.
Bob Draznik
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Author: NorbertTheParrot
Date: 2008-03-19 17:05
Bob -
Altitude per se does not affect pitch. Musical instruments really really really don't know what altitude they are at!
But when we talk of altitude, what we probably mean is ambient pressure, which drops with altitude (of course).
Ambient pressure does not affect the speed of sound, or at least not to any significant degree. This is a scientific fact, let's not debate it.
Reduced ambient pressure makes wind instruments harder to play, because there is less air to work with. I guess that might cause the player to vary the pitch by biting harder or less hard.
But it is clear that altitude does not affect the pitch of instruments in general. This is easy to prove. Buy a tuning fork and an electronic tuner. Check they agree at sea-level. Take them up a mountain. They will still agree. Therefore we must conclude:
1) Either, their frequencies are unaltered, and therefore altitude does not affect pitch.
2) Or, there is some means, hitherto unknown to science, whereby a change in altitude is having exactly the same distorting effect on these two entirely disparate technologies.
If this were not true, an orchestra would have the most terrible problems with its tuned percussion, and any electronic keyboards it might use, whenever it played a gig at altitude.
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Author: tictactux ★2017
Date: 2008-03-19 17:40
> But it is clear that altitude does not affect the pitch of
> instruments in general. This is easy to prove. Buy a tuning
> fork and an electronic tuner. Check they agree at sea-level.
> Take them up a mountain. They will still agree. Therefore we
> must conclude:
> 1) Either, their frequencies are unaltered, and therefore
> altitude does not affect pitch.
> 2) Or, there is some means, hitherto unknown to science,
> whereby a change in altitude is having exactly the same
> distorting effect on these two entirely disparate technologies.
3) The tuning fork vibrates faster because it is less impeded by ambient air, and the resulting higher pitch is miraculously compensated by the altitude lowering the pitch.
--
Ben
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Author: Mark Charette
Date: 2008-03-19 18:12
NorbertTheParrot wrote:
> Bob -
>
> Altitude per se does not affect pitch. Musical instruments
> really really really don't know what altitude they are at!
> But when we talk of altitude, what we probably mean is ambient
> pressure, which drops with altitude (of course).
>
> Ambient pressure does not affect the speed of sound, or at
> least not to any significant degree. This is a scientific fact,
> let's not debate it.
>
Depends on your idea of significance.
> But it is clear that altitude does not affect the pitch of
> instruments in general. This is easy to prove. Buy a tuning
> fork and an electronic tuner. Check they agree at sea-level.
> Take them up a mountain. They will still agree. Therefore we
> must conclude:
> 1) Either, their frequencies are unaltered, and therefore
> altitude does not affect pitch.
> 2) Or, there is some means, hitherto unknown to science,
> whereby a change in altitude is having exactly the same
> distorting effect on these two entirely disparate technologies.
Or - instruments that DO NOT DEPEND on the resonance of a vibrating air column are (essentially) unaffected by the local speed of sound. Density - and the local speed of sound, ergo the resonant frequency of a vibrating air column - is dependent on pressure, temperature, and humidity.
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Author: NorbertTheParrot
Date: 2008-03-19 18:43
Mark C wrote:
"Depends on your idea of significance."
My idea of significance is what is significant to a musical performance. 1% is the difference between A=440 and A=444, and is significant. 0.1% is not.
"Density - and the local speed of sound, ergo the resonant frequency of a vibrating air column - is dependent on pressure, temperature, and humidity."
This statement is true in a literal sense, but is deeply misleading.
The speed of sound in a gas does indeed vary with pressure so long as the density is kept constant. The speed of sound does indeed vary with density so long as the pressure is kept constant. But, for a given chemical composition of the gas, at a given temperature, density and pressure are in direct proportion to one another, and their respective effects exactly cancel out.
It is an observable fact that a given orchestra is able to play both at sea-level and at altitude using the same instruments. If different instruments were affected in different ways by pressure, then there would be a big problem. We have to conclude that:
1. Either all instruments are affected, but to the same extent. This is manifestly absurd.
2. Or, no instrument is affected (significantly) at all.
We can see this must be true without even bothering to go to altitude. At a given location, atmospheric pressure can vary by 10% or even more as the weather changes. Given constant temperature and humidity (as in an air-conditioned room) this has no effect on the pitch of our clarinets.
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Author: skygardener
Date: 2008-03-20 00:39
Sounds like a 'Myth Busters' topic to me.
I am also wondering how much temperature is taken into account in design- considering that, when warmed up, the top is warmer than the bottom.
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Author: Brenda ★2017
Date: 2008-03-20 13:58
OK, then ....
Can we get back to the original question of temperature and humidity? The temp question was answered, but what's the ideal humidity level?
Every time I play in Costa Rica the clarinet feels more stuffy than usual but the humidity is regularly at between 85-90% according to the meter we bought for the house. Temps are about 70 to 85 degrees between day and night (18-26 C.) inland, more like 90 (30-35C.) with high humidity if you're down by the ocean. Once we get back to the capital in the higher elevations and cooler temperatures things respond more like what I'm used to.
My hydrometer has a little blurb on it that shows 70-80% humidity being ideal, but that must be more for people rather than inside clarinet cases. Any thoughts?
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Author: Bassie
Date: 2008-03-20 15:35
Temperature.
When an instrument is warm, it's got warm air in it.
When I go carolling in the bleak midwinter, the brass play /horrendously/ flat. I can only assume this is because the high thermal conductivity of the metal cools the air down more quickly in a brass instrument. Meanwhile I have steam coming out of my clarinet ;-D
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Author: NorbertTheParrot
Date: 2008-03-20 17:49
Bassie. No, that's not the reason. In the same way that carbon dioxide in the breath will lower pitch, so will alcohol vapour. So long as you drink as much as the brass players, all will be well.
Better get in training right away, only nine more months to the carol season.
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Author: BobD
Date: 2008-03-20 18:15
Norbert, you, not me, is the one who is debating....and it seems, losing. I myself have no interest in debating since I'm not as knowledgeable on the subject at hand ...... as you are.
Bob Draznik
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Author: LesterV
Date: 2008-03-21 16:14
The equation for sound speed in a gas indicates temperature, pressure and density are all factors. However, as long a the gas composition remains the same the pressure and density terms become a constant and sound speed becomes dependent only on temperature. The composition of the air within a clarinet varies slightly while being played due to varying amounts of carbon dioxide and water vapor. These minor composition changes are completely unrelated to ambient air pressure so Norbert was quite correct when he stated that sound speed is not significantly effected by ambient air pressure in the context of the discussion.
The air column temperature variations while playing are significant and are dependent on air flow rate. I have measured air temperature variations within the bore near the joint as being between 26 and 31 degrees Celsius while playing a warmed up instrument. Air enters the mouthpiece at the player's body temperature and immediately begins cooling to the instrument's body temperature so the air column is always warmer toward the mouthpiece. The temperature distribution is not constant while playing making the tuning of a particular note slightly dependent on both its duration and what notes were just previously played! The physics of it all becomes very complicated and a well designed clarinet is the result of a lot of compromises made to spread a lot of undesirable effects uniformly over its range to make them the least noticeable. Playing perfectly in tune, if possible, requires learning to actively compensate for these variables while playing. I am always amazed by those that play it well.
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Author: skygardener
Date: 2008-05-31 02:49
New question on this thread-
What is the temperature where YOU play?? In your rehearsal space?? On your stage?? Bring a thermometer with you next time and let us know.
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Author: Ryder
Date: 2008-05-31 21:03
I saw an article by an austrailian college on the acoustics of clarinets. VERY detailed. I don't rember a url though.
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