Re: Proportional Solodant
By Dan Wilson
Robbie said:
[ I wish that the bass and treble softening levers on my Themodist
[ would subdue the accompaniment level a constant amount (in decibels)
[ below the theme level. Then the accents would remain nicely apparent
[ over the full span of my foot-pumping. I imagine a mechanism which
[ would regulate the accompaniment level at a constant percentage of the
[ theme/reservoir level (less the static zero-level of 4-inches or so).
[ Was there ever anything like this: a "proportional Solodant?"
Robbie, you seem to be describing most Themodist instruments here. None are quite the same (as ever in players) but if they are properly adjusted, all of them just allow a two-note chord (all of which is in the treble or bass) to speak with maximum suction on and the subduing levers hard over to the left. A three-note chord should be on the point of failing.
Right. Let go the levers and if the THEMODIST switch in the spoolbox is on, there will either be no or very small additional power from "themed" notes. As you move the levers over, they gradually suppress the power in one half of the instrument (the higher lever in the bass, the lower one in the treble, so you can operate both with the left thumb if you like), except that "themed" notes are always at your pedalling strength. Or something like it - later instruments "theme" better.
Thus if you are holding the levers over any distance and pedalling at fail point, the regulator ensures the piano still plays but there's no theme effect. If you're pedalling gently, there's some theme effect. And if you're busting a gut, the thing begins to play like a Duo-Art and is _wonderful_. I've done a roll of Rachmaninov's 2nd Sonata (to answer pedants, four rolls - both versions) and the opening requires a loud accompaniment in the treble and a very loud theme in the bass, with everything too close together to be able to accent with the feet. This is an ultimate test of a well set-up instrument. A fixed- suppression-level Solodant machine would give you only the two options of shutting the right hand down to almost nothing, or failing to separate the hands at all, and would be useless/// er, disappointing.
Which describes your instrument ? Aeolian did occasionally cheat and provide levers which merely operated pop valves, producing all-or-nothing suppression (I don't know why - maybe it was a cheaper option) but all the American Strouds, Stecks and Webers (and Steinways) I've met have the proper gear and work if anything better than the British equivalent. Most restorers here only have a dim idea of what "theme" is about, but they usually do a Chinese copy of what they find, so the slide valves work once you have sorted out the adjustments and, often, a couple of tubes crossed since new (!).
Dan Wilson
[ In my (American) Aeolian Themodist the accomp regulator vacuum is fixed
[ with a spring, and the slide valves are a crude variable bleed to the
[ theme supply. I'd much rather the accomp vacuum were a _regulated
[ percentage_ of the main reservoir vacuum. A slide lever won't do this.
[ Have you ever seen a regulating mechanism which could maintain
[ a constant proportion? -- Robbie
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