[pianotech] Pianola player...plastic parts?

[Ron Nossaman]

I've actually rebuilt one of these Aeolean player stacks, but I'm cured 
since. Aversion therapy works. Though there was crude junk back there 
too, the decent quality old (real) players of the 1920s were decently, 
sometimes marvelously engineered, possessed of leather valve seats, and 
assembled with real attention given to tolerances and function. Leather 
is an ideal valve material, as it conforms to the valve seat after a 
short while, and is a good tight seal for many years afterward without 
needing elevated pressures to achieve it. Building player stacks through 
the 20s was relatively expensive, and demanded a trained work force 
capable of doing skilled close tolerance work and caring about doing so.

The resurrection of the player by Aeolian came with a different set of 
priorities. The valves, for instance, were three stacked injection 
molded plastic pieces, held together by what appears to be a 
plastic/acetone glue, slavered on with minimal care, and a stamped 
neoprene disc as a valve. Neoprene doesn't compact like leather and 
improve the seal over time. It remains as un-flat as it was, requiring 
high pressure levels to seat with each stroke, and becoming worse 
through the years as the material stiffens with age. The valve gap, 
unlike the old decent quality players, is whatever results when the 
valve is assembled, and tends to be overly wide. The result is that they 
are very wasteful of available vacuum, and can be heard to gasp and pop 
as the player is used. Aeolian's basic approach was to make a player as 
cheaply as possible that could be put together by minimum wage warm 
bodies with absolutely minimal training, and produce a mechanism that 
was cheap enough to be disposable, requiring virtually no QC during the 
assembly, that finally worked at a just barely adequate level as a toy 
for the consumer market at the price it cost. As an example of 
industrial design of a low end product, it's excellent. As a player, 
they're adequate for most people, who don't know the difference. For 
someone who's rebuilt real players, and seen them operate at vacuum 
levels under 4" (water), they're total junk.

Ron N