merits of the square pianos

[Steve Pearson]

Herewith some opinionated opinion from a piano tech who is also a string player.  (definition of a string player: someone who hangs around with musicians).
The subject of the Square Piano as a viable musical instrument gets to the core of a number of issues, not just histerical (sp) tunings.  Many years ago, I played with a local chamber ensemble which took on some 19th century American music.  For the piano, we opted to use an old square grand.  The make escapes me, but it had been lovingly restored by a local afficionado of those behemoths.  The immediate reaction on the part of the pianist was something like, "Oh my....this sounds like (expletive deleted)."  We string players, as well as the quartet of singers engaged for the occasion were at once intrigued and then relieved that we didn't have to work so hard to be heard.  The somewhat lighter,  relatively transparent tone made balancing the small string ensemble as well as the vocal quartet as simple as could be.  Eventually the pianist was convinced as well. She was able to cut loose a bit more, and didn't always have the feeling she would have been better off in the next room. I believe it was Nicholas McGeegan of Philharmonia Baroque orchestra who was addressing this subject in an interview on public radio several years back.  He was speaking of harpsichords, but the same logic applies to the square, or the fortepiano, or whatever.  While not an exact quote, here is a close approximation:  "There are problems associated with using period instruments with instrumental ensembles.  Fortunately, they are the right problems."     Anyone who has ever played a Beethoven Piano trio with a 9' concert grand knows the problems of balancing violin and 'cello with the piano are nearly insurmountable. So much energy is spent in trying to balance the three hopelessly missmatched instruments one wonders what ends up sacrificed to simply achieve balance, that would have fallen quite naturally out of the music had the instruments  been on a more level playing field.  It is not a question of whether music can be made in these circumstances, rather the nature and character of the problems associated with making the music happen
JMHO, 
Steve Pearson