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Theme Problems in 65/88-note Themodist Grand
By Spencer Chase

Greetings,  I have just finished installing a 65/88-note Themodist
player in an early Weber grand.  This was a very difficult rebuild
due in large part to many years of modifications, substitutions of
parts, use of silicone epoxy and just about every other wrong material.
Parts were installed up side down and critical settings ignored.  The
original design was not engineered with rebuilding or even maintenance
in mind.

It is finally working pretty close to correctly.  I copied the tubing
as I found it and there were some errors which were easy to spot and
correct, but one possible error remains.  The theme system does not
seem to be operating properly although the theme primaries do open
and switch the secondary pouches between vacuum and atmosphere as they
should.  However, the theme accenting is unpredictable and the sound
of the theme secondaries switching is feeble.  The theme valves are
connected to their proper sides so this is not the problem.

In the Duo-Art, the theme primaries are operated from unregulated
vacuum so as to always be as high as the theme regulator vacuum.  The
way this piano was tubed, the theme primaries are supplied from the
regulator that serves the sustain pedal and the note primaries.  Is
this correct?  From the fittings in the piano there is really no other
way to connect it, but someone has definitely gone to great trouble to
make other things not work by substituting and modifying parts.

How could the theme secondary operate if the suction to pull the pouch
down is less than the suction pulling it up?  Does anyone have a tubing
chart for one of these or a working example from which to determine how
the theme primary (and sustain pedal primary valve) are to be connected?

One other question about playing the system and what to expect.  The
whole piano operates on chest vacuum unless the subduing lever for bass
or treble is operated.  There are no regulators for the subdued vacuum
levels.  They are reduced with a slide valves and a somewhat crude
linkage.  This seems to require quite a bit of skill to maintain a
fixed playing level as it seems to vary with stack demand and pedal
pressure which must be varied to control the theme.  Of course, with
the theme not operating properly I do not know how it will work once
everything is working correctly.  Is this just the way the subdue
levers operate.  Is it just a mater or practice or is there something
I am missing?

Best regards,
Spencer Chase
Laytonville, Calif.

(Message sent Mon 1 Mar 2004, 07:43:45 GMT, from time zone GMT-0800.)

Key Words in Subject:  65, 88-note, Grand, Problems, Theme, Themodist

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