Re: [Harp-L] Fatigue and Reed Life: An Objective Test?

"Vern Smith" <jevern@xxxxxxx> · Fri, 18 Apr 2008 20:09:02 -0700

----- Original Message ----- 
From: "Brendan Power" <bren@xxxxxxxxxxxxxxxxx>

To: "Harp-L" <harp-l@xxxxxxxxxx>

Sent: Friday, April 18, 2008 2:33 PM

Subject: [Harp-L] Fatigue and Reed Life: An Objective Test?
......It seems there is a lot of anecdotal evidence (but an equal amount 
of

factual uncertainty) about the reed longevity of different harmonica

brands that reminds me of another Great Harmonica Debate: the one over

comb materials. That one was put to a couple of pretty decisive

blindfold tests a few years ago.................
If reedplate thickness could be eliminated as a factor, I wonder if an
objective test could be devised for reed life? ................

Getting a single player to do all the tests would be a bit tricky, as
there would be tiny variations in his/her embouchure and breath pressure
over time that would invalidate the results..............................

There is a major difference between blind comparisons for materials effects 
and tests for reed life.
 In the materials comparisons, we  test the ability of people to perceive 
any differences in tone arising from differences of comb materials. The 
skeptics do not claim that there are no differences at all;  just that they 
are so slight that people cannot hear them.
In a test of copper-alloy vs SS fatigue, we are testing the reeds themselves 
and not the ability of people to perceive their failure.  No one will 
disagree over whether a reed has gone seriously flat and/or cracked.
IMO, the ideal test would be to connect twenty or more reedplates of each 
material type to a pump which would sound them continuously. (What a 
cacaphony!)  Maybe push them hard at 10 in. H2O pressure...about twice 
"cruising speed" pressure for the average reed.  Then measure the time it 
takes for half of the reeds in each group to fail.  The difference in these 
times would be a meaningful measure of the difference of the material's 
tendency to fatigue.
Separate data could be collected on reeds of the same pitch.
Any test using just a few reeds would be subject to errors arising from 
reed-to-reed variations among those of the same material.  Tests using human 
players would exceed their endurance and would introduce many spurious 
variables.
Vern

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