Soundboard crown

[Richard Brekne]

Calin Tantareanu wrote:

> Hello!
>
> I have followed the numeorus discussions on this list oabout rib-crowned vs.
> compression crowned soundboards with great interest.
> However, I am asking myself if a soundboard always needs  crown in order to
> work properly?

No... tho that is dependant to some degree on what you mean by "work properly"

> I heard about some old pianos with no measurable crown that sound very good. I
> have even seen some where no crown seemed left, yet the performance was very
> good

I'm sure you have. I have also seen a couple instances of pianos with reverse
crown, or caved panels that sounded actually quite nice.

>
> I read that harpsichords do not have crowned boards (except the Italian ones).

Some harpsichords or cembelos have rippled boards, tho despite a couple cembelo
builders comments on the subject, I am still unsure of just why. But in anycase
they do not in general crown boards as piano makers do. An exception to that
rule is this monster instrument we have at the University. It uses real crown, a
huge size soundboard (for a cembelo) and really thick strings. I believe the
idea was to get more power out of the instrument concept. It is not a very
popular instrument. I will see if I can get our Cembelo teacher/tech to write me
up a description about it so I can post it to the list.

> So, why is a crown necessary? Would a flat board, but with enough downbearing
> for teh strings, work or
> not?
>

I think you have to remember that most "flat boards" started off with some form
of crown, and quite probably those that sound good today had probably a
reasonably decent life with regards to climate and maintanance, and likey have
just enough downbearing left to avoid some mismatch in the way strings and panel
intereact to create the sound we hear.

That being said... I suppose you could build a flat panel, match a string scale
to it and come out with a useable result. Tho I think it would probably be the
most powerfull of instruments. I think also it would have some trouble when the
climate became significantly more dry then it was when it was built.

I always enjoy this kind of question coming up. You nearly always get a lot of
good replies that make for good reading.

Cheers
RicB

> Regards,
>
>  Calin Tantareanu
> ----------------------------------------------------
>  http://calintantareanu.tripod.com
> ----------------------------------------------------

--
Richard Brekne
RPT, N.P.T.F.
UiB, Bergen, Norway
mailto:rbrekne@broadpark.no
http://home.broadpark.no/~rbrekne/ricmain.html
http://www.hf.uib.no/grieg/personer/cv_RB.html