 The Clarinet BBoard
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Author: george
Date: 2003-10-20 22:31
Could someone tell me ( or tell me where to find) exactly what determines the "strength" of a reed? I gather that the numbers 3, 3 1/2, etc., are not absolute measurements since they seem to vary from manufacturer to manufacturer--but what exactly is being measured and how is it measured?
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Author: BobD
Date: 2003-10-21 13:11
My impression has always been that it is a measure of stiffness.....i.e. resistance to vibration(not the true engr. def. but descriptive). There is probably some relationship to Young's Modulus of Elasticity but it probably varies among manufacturers and maybe even models within one mfgrs. lineup. It would appear that YM varies rather widely from cane to cane. These are, of course, opinions.
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Author: Markus Wenninger
Date: 2003-10-21 17:43
yes , that´s right, what BobD said about "stiffness". It is a pure scale referring to the thickness of what in German is called the "heart" of the reed, this more or less heart-shaped centre of the reed (sorry, I just don´t know the English term for it). And they vary form brand to brand , most certainly.
markus
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Author: Henry
Date: 2003-10-21 17:46
So the scale is not so "pure" after all.
It would be nice if there were the equivalent of an ASTM method that is accepted by the whole "industry".
Henry
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Author: Mark Charette
Date: 2003-10-21 18:08
Markus Wenninger wrote:
> yes , that´s right, what BobD said about "stiffness". It is a
> pure scale referring to the thickness of what in German is
> called the "heart" of the reed, this more or less heart-shaped
> centre of the reed (sorry, I just don´t know the English term
> for it).
That's not correct, at least not correct when I've seen reed strength gauges. They measure bending resistance, not thickness. Bending resistance is not the same as thickness.
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Author: Mark Charette
Date: 2003-10-21 18:12
Henry wrote:
> So the scale is not so "pure" after all.
> It would be nice if there were the equivalent of an ASTM method
> that is accepted by the whole "industry".
And what company could afford to send a representative to the annual weeklong national meeting, and then send a rep for the annual weeklong international meeting?
Mark C., former member of ANSI X3H3.1 and sometimes assistant to the ISO rapporteur.
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Author: Henry
Date: 2003-10-21 18:14
Yes, Mark, I guess it's not like selling mass products like laundry detergent or engine oil!
Henry
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Author: L. Omar Henderson
Date: 2003-10-21 18:54
(Disclaimer - this research is proprietary) It is possible to characterize reeds through their vibrational characteristics and expressed in a narrow frequency range. A machine (highly automatable) which appies a known force to the clamped bottom section of the reed and a vibrational detection system at the tip of the reed would yield a frequency measurement of some portion of the tip area of the reed. This machine could be easily quality controlled for temperature, atmospheric presssure, and relative humidity through sensors and software. A vibrational standard set could check instrument calibration. Reeds within a box could have a label with the frequency range, and mode of frequencies within the box. This would involve setting some frequency range standards for current reed strengths but then everyone would know that whatever reeds they were getting were within a certain frequency range. The frequency range for different strenghts would be overlapping spectra but a tighter spectrum would be desirable. Reed strength, or frequency, of course has nothing to do with ultimate playability, longeivity, or sound quality produced by the reed. The potential market is small for such a machine.
The Doctor
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Author: Henry
Date: 2003-10-21 19:01
Welcome back, Doc! I haven't "seen" you for a while. As to the above post, your last two sentences seem to effectively kill my idea of a genereally accepted industry test.
By the way, my cork grease is running out. Will be in touch with you shortly!
Henry
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Author: hans
Date: 2003-10-21 20:37
The idea has appeal, but for the American Society for Testing Materials to establish a test, I expect that the test would have to meet standards for repeatability and reproducibility. IMO that might be difficult, although it might be feasible for plastic reeds.
ASTM tested/approved reeds would probably be very expensive too.
Hans
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Author: BobD
Date: 2003-10-21 21:16
Incorrect is correct, Markus. I didn't mention thickness. With most engineering materials resistance to elastic bending varies directly with thickness. But my impression is that two pieces of cane the same thickness can have different stiffness. Why this is so probably is a function of age, growing conditions and other variables beyond my knowledge.
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Author: David Spiegelthal ★2017
Date: 2003-10-21 21:25
Doc, your idea has merit, but (if I understand your concept correctly) the results would only be valid for what we call a 'fixed/free' vibrational mode, which completely disregards the presence of our mouth on the reed --- the mouth provides a somewhat distributed damping effect which exists along a certain portion of the reed and varies with every individual --- since the majority of a reed's vibration (in real use) occurs between that damped area and the tip, then a measurement of the vibrational characteristics of the full-length, completely undamped reed by your machine, would be very hard to correlate with real-life performance. Certainly it won't capture the very significant difference in 'stiffness distribution' between various reeds, that is, some reeds have thick shoulders but thin tips, some reeds are more uniform in thickness from heel to tip, etc. And a single value or small set of discrete results wouldn't tell the whole story either, we'd have to look at many sets of time- and frequency-domain plots to characterize a reed accurately. I'm not sure if this is making much sense, but it's a very complex problem, which is why a good solution hasn't been made available (yet).
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Author: L. Omar Henderson
Date: 2003-10-22 03:07
There are many caveats and this is a futuristic scenario based (although prototype tested) idea. The ideal and the practical differ greatly when it comes to reeds. What we have now is a reed stiffness or flexibility standard arbitrarily applied by each reed manufacturer using numbers, letters, ranges, or combinations of these grading systems. Reed comparison charts are of some help but the embouchure of each individual, the architecture of the mouthpiece used, the barrel, the horn itself, etc. all add variables - along with the intrinsic characteristics of the cane, the shape and cut of the reed.
At least a vibration measurement in the tip area (this would also have to be determined to encompass the area vibrating against the rails of an average MP window) would remove, or compensate, for the characteristics of the reed including structure, shape and cut. All of the other variables would still come into play. IMHO this measurement is more analytically valid than a stiffness measurement - not the absolute - but a definite improvement over the hodge-podge of current reed grading systems. So who cares?? - The overall improvement in the musician consumer's knowledge about their products and accessories is IMHO a worthwhile goal. It would also potentially save the consumer money while trying to find a new reed to play.
As indicated, if there were compensatory elements (corrections for atmospheric pressure, altitude, temperature, and relative humidity) and a calibration procedure with calibration standards there would be more consistency in measurements of reed's "strength" then now available. Many medical testing devices have self-calibration tests built into the machines, which automatically calibrate (or tell you what is out of calibration) when the machine is turned on. You could take this to an extreme with ASTM type regulation or international inspectors but there is a spectrum of self-quality assurance to absolute regulation. Many manufacturers in other areas voluntarily (or do so from market pressures) standardize their products for consumer ease of choice and sale ability.
The Doctor
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Author: Brian
Date: 2003-10-22 10:14
Mark,
What you said about the weeklong meetings, etc...for what they charge us for reeds they SHOULD be able to send they're reps!!!
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