[ Bob Hodge wrote in 140623 MMDigest --

> I'd be grateful if someone could tell me what the manufacturers
> used when this was built.  Clearly it wasn't Luan ply!

I would venture that the wood was not a multi-ply wood.   Also,
I suspect the grain ran crosswise (perpendicular to the length of the
music rolls).  I have seen some cabinets with small lips on the front
of pull-out drawers, which add stiffness.  You could also glue wood
stiffeners under each shelf yourself.

Larry Toto