Hello,  We had a problem with the air conditioning machine.  A large
Polyphon, made for bars, was damaged, and in the back you can see today
a long crack.

The expert has asked, if all the Polyphons were made in the same way,
[that is,] the furniture [the case] and its back with the wood panels
[the grain of the wood] always up and down, and not crossed like
plywood.

If they are always the same with the wood panels up and down, why?
Perhaps for the sound box effect?

What is the function of the two large wood pieces in the back?  Perhaps
to maintain the back under tension?

Thank you for your answer,
With my best regards from France
Francoise Dussour
fdussour@club-internet.fr