Grand Rim Construction

[Ron Nossaman]

>Is the answer the dense maple reflects more sound back onto the strings and
>soundboard I ask myself.  Surely 'select hardwood' covered in polyester on
>both sides is a pretty dense and reflective surface so this doesn't seem to
>explain it to me.
>
>Regards,
>John Woodrow
>Sydney, Australia ICPTG 

Hi John,

Yes, that's correct. The rim doesn't make nearly as good a soundboard as a
soundboard, hopefully, so the less energy it steals from the board, and the
more it reflects back into the board, the better. The polyester is just
sitting on the surface, and doesn't really have a lot to do with it. It's
the body of the structure that counts. Maple, being stiffer, harder, and
denser, steals far less energy from the board. 

It's occurred to me that impregnating a "select hardwood" rim with a
polymer of some sort could improve performance, but it would be costly and
raise other problems of glue bonds and overall weight. It would also negate
the main benefit of using "select hardwood" in the first place - speed and
ease of fabrication. The characteristic sound difference is the trade off.

I'd love to get one of these pianos in the shop for a work over. I've been
mulling over some "not ready for public scrutiny" ideas that might help.
Maybe I'll get to try them out eventually.


Ron N