On p. 32 of the MBSI's current issue (July/August 2015) of its journal
"Mechanical Music" there is a statement that music box discs made of
different materials produce different tones when played.

Can this be true?  I never imagined such a situation.  I know that
discs are made of zinc, steel, fiber, and other materials, but how can
the material a disc is made of affect the sound produced by the musical
comb?

Matthew Caulfield
Irondequoit, New York