David Dewey's comment (MMD 140222) about loss of downbearing affecting
the tone in the bass end of the Mason & Hamlin made me reflect on the
role of the "tension resonator" in Mason & Hamlin pianos.  This device
is meant to resist changes in the piano by pulling the sides in using
rods that are similar to turn-buckles.  I have never heard any
discussion of it use or adjustments made after the factory setting.

My Mason & Hamlin RA 36231, likely from late 1927, has a "6" and an
"A" molded into the plate.  Has anyone collected data on string scale
vs. date of manufacture?

Bill Chapman - in sunny but very dry La Quinta, California