 The Clarinet BBoard
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Author: BAC
Date: 2000-09-05 02:24
Well I guess the next question is - when the air column is moving down the clarinet, will it bounce off the wall at: different angles, different speed? Is all of it transmitted? Would any of this depend of material - wood verses glass verses plastic verse wood composit verses metal? Has this been tested?
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Author: BAC
Date: 2000-09-05 02:25
Sorry - not sure how this started a new topic - Mark feel free to move it to its proper place.
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Author: Mark Charette
Date: 2000-09-05 02:40
BAC wrote:
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Well I guess the next question is - when the air column is moving down the clarinet, will it bounce off the wall at: different angles, different speed?
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It's what is called a "standing wave".
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Is all of it transmitted?
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No. It's relatively inefficient.
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Would any of this depend of material - wood verses glass verses plastic verse wood composit verses metal?
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That's what we've been talking about. The vibration of the material is insignificant vs. the vibration of the air.
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Has this been tested?
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Yes.
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Author: Eoin McAuley
Date: 2000-09-05 08:04
BAC wrote:
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Would any of this depend of material - wood verses glass verses plastic verse wood composit verses metal?
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Mark Charette wrote:
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That's what we've been talking about. The vibration of the material is insignificant vs. the vibration of the air.
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But what about reflection? Never mind vibration in the wood, does the surface of the wood (hard gloss, deep wood grain) affect the reflection of sound and therefore the quality or amplitude of the tone?
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Author: Bob Sparkman
Date: 2000-09-05 09:33
I would ask Clark Fobes.Eoin McAuley wrote:-------------------------------BAC wrote:-------------------------------Would any of this depend of material - wood verses glass verses plastic verse wood composit verses metal? -------------------------------Mark Charette wrote:----That's what we've been talking about. The vibration of the material is insignificant vs. the vibration of the air. ----But what about reflection? Never mind vibration in the wood, does the surface of the wood (hard gloss, deep wood grain) affect the reflection of sound and therefore the quality or amplitude of the tone?
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Author: Don Berger
Date: 2000-09-05 15:02
Going in to acoustics, to me , is like the woods before the jungle begins! Try Gibson, Benade, Helmholtz 's etc discussion , practice and theory. Some of my thoughts, the speed of sound is about 1100 ft/sec [I use it to see how close the lightning flash was], and yes, reflection from hard surfaces occurs, ever sing in a shower? Yes, "standing" waves {areas of compression and rarefraction [sp?] } are what we depend upon, as evidenced by register vent location and effect. Over my head!! Don
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Author: Mark Charette
Date: 2000-09-05 17:44
Smoothness, roughness, etc. are not a strict material properties since they can be emulated. There are effects known to be present by other than material properties; that area begs a lot more exploration.
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Author: Roger
Date: 2000-09-05 17:53
People seem to believe that flutes made of wood have different tonal qualities (not any more or less in tune however) than those made of silver, etc. If this rule applies to flutes, why not clarinets?
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Author: Mark Charette
Date: 2000-09-05 18:27
Roger wrote:
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People seem to believe that flutes made of wood have different tonal qualities (not any more or less in tune however) than those made of silver, etc. If this rule applies to flutes, why not clarinets?
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It's not a rule. "Seem to believe" is operant here. Roger, you're going to have to delve really deep and come up with some good, hard evidence. There is some - check the Klarinet archives for a number of references I posted recently to some in-depth studies done by some well-known researchers.
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Author: Roger
Date: 2000-09-05 21:15
The following is a statement from the Haynes flute webpage about their wooden flute
The unmistakable sound of this Haynes Wood Flute is rich and dark. .
The following is statement from the powell website about their wooden flute:
The wooden flute resulted from a response to requests from some internationally acclaimed flutists, such as Andras Adorjan, who find that they prefer to perform or are being required to perform certain music on a wooden flute. They were particularly concerned that they have a wooden flute which had all the tonal qualities of the traditional wood instruments, but had all the scale and mechanical accouterments of the modern Boehm flute.
It is apparent that flute players believe that the material makes a different. (They may just feel it, but feelings sometimes are translated into playing---a self-fulling prophecy.)
This is not the other Roger. By the way, has anyone detected a tonal difference between a Rosewood clarient and an African blackwood clarinet?
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Author: Joris van den Berg
Date: 2000-09-05 22:05
From a student fluid & gass dynamics (I hope this doesn't get too technical).
By the amount of air that is blown into the instrument and the diameter of the bore, one can calculate the so called Reynolds number (if anyone is interested i could detail on this).
The Reynolds number indicates wether the stream of the air is laminar or turbulent. The collumn is most certainly laminair (actually the hiss noise that can sometimes be heard is a little bit of turbulent flow).
Laminar flow means the aircollum is moving according to the tube. Air that is in the middle of the tube stays in the middle, and air that is close to the wall stays close to the wall.
Conclusion: no 'bouncing' what so ever will occur.
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Author: Joris van den Berg
Date: 2000-09-05 22:08
Wood or metal is different from Wood versus plastics because the metal is so thin it will have resonance frequenties in the region of the produced tone. This means the metal itself will start to produce sound. This in contrast to thick-walled wood wich has much lower own frequenties and therefore will not resonate to the produced tone.
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Author: Mark Charette
Date: 2000-09-05 23:28
Roger wrote:
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The following is a statement from the Haynes flute webpage about their wooden flute
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Manufacturers use puffery to describe their instruments. It's meaningless (for some of the most laughable phrases, see the Leblanc literature ...).
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Author: Mark Charette
Date: 2000-09-05 23:32
Joris van den Berg wrote:
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From a student fluid & gass dynamics (I hope this doesn't get too technical).
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Joris,
there is non-laminar from from the mouthpiece to at least the barrel (there's tip-vortex shedding, tip flutter, and a non of non-linear effects in those first few inches).
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Author: Mark Charette
Date: 2000-09-05 23:33
Joris van den Berg wrote:
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Wood or metal is different from Wood versus plastics because the metal is so thin it will have resonance frequenties in the region of the produced tone.
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This is not true of flutes or metal clarinets - both have measured wall vibrations greated than -60 db. Same with organ pipes.
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Author: Joris van den Berg
Date: 2000-09-06 08:30
Mark wrote:
there is non-laminar from the mouthpiece to at least the barrel (there's tip vortex shedding, tip flutter, and a non of non-lineair effect in those first few inches).
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Reynolds number indicates what the natural way of the flow would be given enough lenght of pipe. The amount of lenght varies by the amount of turbulence created at the inflow. If the remaining turbulance would get further then just the barrel no standing wave would be formed (pressure gradients in turbulent flow aren't constant enough to produce anything other than noise). Of course there will be a little turbulence around the toneholes locally.
Could you specify any of those non lineair effects? Because the ones i can think of are by far too small to matter (compression of the fluid due to the motion of the reed?). By the way, turbulence is in itself non-lineair (to be precise, it's chaotic)
Greetings, Joris
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Author: Mark Charette
Date: 2000-09-06 11:41
Joris van den Berg wrote:
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Mark wrote:
there is non-laminar from the mouthpiece to at least the barrel (there's tip vortex shedding, tip flutter, and a non of non-lineair effect in those first few inches).
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Reynolds number indicates what the natural way of the flow would be given enough lenght of pipe. The amount of lenght varies by the amount of turbulence created at the inflow. If the remaining turbulance would get further then just the barrel no standing wave would be formed (pressure gradients in turbulent flow aren't constant enough to produce anything other than noise).
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That's why I limited my statement to the first few inches - the mouthpiece/barrel combination.
Check the Musical Acoustics Research Library at http://ccrma-www.stanford.edu/CCRMA/Collections/MARL/ for the references. Somewhere in the Coltman, Backus, or Benade collection (sorry, I don't have a link the the relevant articles around, but I'll bet you'll have fun in there anyway!)
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Author: Roger
Date: 2000-09-06 12:42
I found on line once a flute repair manual. One of the chapters was an exhaustive comparison of how tone was formed in the flute vs. the clarinet. (I have a copy on my computer and will post the url later. In another chapter the manual has a discussion on flute materials (silver, gold, etc.) It indicates that there has been at least one study that concluded that flute materials make little difference.
this manual makes for interesting reading.
Perhaps the alleged difference in tone of wood v. plastic has to do with the quality of the instrument. (Note the above study also found different flutes (same brand) of the same material differed in tone quality.
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Author: Don Berger
Date: 2000-09-06 16:22
Its been a long time since I had reason to consult my Chem. Engr's. Handbook, since I USED to know some of it! When I find my Gibson, I'll bet he has something to say about eddy currents and other turbulences in our horns. Also my OLD Broadhouse P B's "Musical Acoustics, The Students Helmholtz" must go on at length! If I find anything more significant than "keep the cl's bore as smooth as possible [no"steps"]" , I'll post it! Don
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Author: Mario
Date: 2000-09-07 17:02
This is an interesting thread indeed. It touches most of the key items (in particular the excellent literature on the subject). I like the Benade's book as being the clearer of the bunch - enough math to help me understand, not so much to distract from the content.
However, the science of acoustics remain imperfect. There is not mathematical model that can described at the very fine level (say, at the molecular level) what is happening. So, everything we read on the subject is a first or second order aproximation. Essentially, the maths modelling a cheap instrument and the match for a top of the line one are the same.
So, why are instruments all different? Because they are imperfect at the molecular level. No two instruments are the same. The refined attributes of great instruments are a side effect of the presence (or lack) of minute imperfections. Craft"persons" learn empirically what works and what does not and pass their art to apprentice. There is no mathematical model that describes why a Rossi is so different from a Wurlitzer for instance.
There is no theory at the moment that can explain why Stradivarious violins sound the way they do.
There is no theory that can explain why a particular dish tastes better than some others (even taste is aways a combination of 4 senses).
There is no theory that can explain why a wrinkle here in a sail (on a saiboat) helps what a wrinkle there is a hinderance.
There is no theory that can explain why a particular combination of colors in a painting will please the eyes, while others will not (again, this in spite of the fact that we are always using the same 4 colors).
Somebody once said that what is truly artistics is where sciences stop and unmodelled imperfections take over. Things are beautiful in a tiny slot just at the edge of formal science, and just at the edge of random chaos.
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