Soundboard stiffness vs. string coupling

Richard Brekne Richard.Brekne@grieg.uib.no
Tue, 25 Jan 2005 16:29:10 +0100


Vladan

I thought for a moment I had understood where you were going here, but 
perhaps not. The below assesment is essentially correct. The amount of 
energy the string gives to the soundboard is not changed by the amount of 
clamping... beyond the point where it is clamped enough.  Its downbearing on 
the soundboard changes to some degree the impedance of the soundboard, and 
so one can better or worsen the situation between the string and soundboard 
in by changing downbearing. But that is in itself independant of the 
<<optimal>> amount of stiffness that particular board has.

You can change the bleedoff the duplex in a sense is, both front and back 
for that matter. Whether this can be called lost energy or redirected energy 
is evidently up to the beholder.


Cheers
RicB

>> Good, I see what you are saying.  That leaves then the
>> rear duplex length as a means of adjusting the amount
>> of energy coupled into the soundboard.
>>
>> I will play with the Accujust setting.
>>
>> Thanks,
>>
>> Vladan
> 
> 
> 
> Hi Vladan,
> You lost me again. The soundboard is coupled to the string by being 
> clamped to the bridge, which is glued to the soundboard. Adjusting the 
> bearing changes the downbearing loading on the board, changing the 
> apparent stiffness of the board, which changes the impedance mismatch 
> between the strings and the soundboard assembly.
> 
> 



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