Re: Themodist (000323 MMDigest)

In-Reply-To: <200003251839.KAA00901@cohost.foxtail.com>
Philip Jamison asked:

> How exactly does the Themodist work? They have 2 levers (on the pianos
> I've seen) which, when pulled to one side, make the piano play
> softer. I assume the stack is divided and the Themodist holes accent
> individual notes or chords. I've never seen one that actually does
> this, however. Does the piano play at a medium volume and then "forte"
> when an accent hole appears? Must the levers be used during a
> Themodist roll?

Unrestored instruments (and, I'm sorry to say, some "restored" ones I've
seen) commonly have the "theme" ports and/or primary valve pouches
clogged with dust. The knife valve settings for treble and bass subduing
are difficult to disturb seriously, but the spring settings for the
treble and bass regulators - which level out the suction to create a
similar striking strength for single notes and notes in chords - are
very often wildly wrong so that subduing scarcely occurs.

I estimate that only one in four player restorers really understand what
is needed to make Themodist work properly. It isn't even as much of a
black art as the proper tubing-up of four-hole tracking. I once
dismantled a Stroud Themodist upright in Mary Belton's "Original Pianola
Shop" in Brighton to find out why its "theme" performance was so poor -
and found that the treble and bass theme tubes had been crossed over
from new !

Normally, the springs are set so that with the subduing levers hard
over, a two-note chord on that side of the keyboard will just play
reliably.  This is why Themodist test rolls usually have notes arranged
in rising and falling thirds. As the chords cross over the central
divide, the strength should remain the same.

Even with the help of Themodist, it takes some determination to achieve
the very prominent melody and supporting accompaniment strengths that
pianists produce and Duo-Art achieves with its much higher suction.
Trying to understand the dynamics of piano playing with a player piano
in front of you resolutely trying to level them all out is a long and
arduous path. But playing a new Steinway concert grand with a 1912
Themodist pushup is as near as I've ever got to trying heroin.

Dan Wilson, London