NEWS FLASH! "Conover clobbers Steinway !"

[Farrell]

Ditto, ditto, and ditto.

Terry Farrell

----- Original Message ----- 
> I've never understood the importance of sound travelling through the
> soundboard parallel to the grain and across the grain.  When we "hear" a
> piano, we're sensing air pressure differences, which are created by the
> diaphragmatic movements of the board.  Wogram states clearly in the
> excerpts you provided, that the ribs are there to equalize the stiffness 
> of
> the board across and parallel to the grain, to optimise the diaphragmatic
> response.  He says nothing about the speed of sound transmission throught
> the wood, at least in the excerpts provided.  Where does this idea come
> from?
>
> Your online dictionary gives transmission speed as ONE EXAMPLE of
> anisotropism, but Wogram is specifically referring to bending stiffness,
> not transmission speed, as the anisotropic property being influenced by 
> the
> ribs.
>
> I was watching Andre Bolduc's taped class on soundboard replacement the
> other day, and he talked about the treble "reflector".  On S&S 
> soundboards,
> this strip of maple is attached to the beveled end grain of the soundboard
> at the high treble end, according to Andre it's to keep the sound from
> leaking out of the end grain.  Huh??  Where does this idea come from?
>
> Mike
>
>
>> [Original Message]
>> Prompts me to ask a bit about an idea being thrown around in an off list
>> dialoug I am having with a couple folks. The idea is not mine but it
>> sounds intriguing.  Let me throw this at you (and whomever else might be
>> interested to comment). I'll let the fellow who threw this at me speak
>> up for him/her self if they so choose.
>>
>> The primary acoustic function of the ribs is to transfer sound cross
>> grain more or less as fast as it otherwise buzzes along the grain.  What
>> if we could make a soundboard with enough crown support perpendicular to
>> the bridge without support  from the ribs (or nearly as much as we use
>> in todays instruments) ?
>>
>> The idea that strikes me as being able to perhaps do exactly this is to
>> allign the grain perpendicular to the bridge, and construct a
>> pre-crowned soundboard panel of several laminants, all with grain going
>> the same direction. With the grain going perpendicular to the bridge and
>> what crown support the unribbed soundboard would have, cross grain
>> ribbing would be able to do their acoustic job and provide a bit of
>> extra support to the curvature of the wood while being of much smaller
>> dimensions.  In addition... the bridge itself would function like the
>> ribs in speeding sound cross grain.  It might be a way of approaching
>> the different requirements of the bass and high treble areas.
>>
>> Cheers
>> RicB