Re: Duo-Art Playing Too Loud
By Robbie Rhodes
Pete, a 3-bar linkage connects the Duo-Art accordion stack to the shaft of the knife valve. It imparts a very non-linear relationship between the accordion movement and the regulator shaft movement, and the adjustment has a very big effect. The design was an attempt to achieve a logarithmic relationship, so that each little dynamic step would produce a consistent change in volume (like about 1.5 decibels). Unfortunately, when the linkage is adjusted for the nicest-sounding logarithmic response, the vacuum regulation is poorest, and big chords will not play.
Try this: loosen the clamps at both ends of the linkage while you hold the respective shafts from turning. Move the linkage position and tighten the clamps again. Listen to your test roll as it checks the piano through all the intensity steps.
I admit I'm a bit hazy about the linkage details -- at has been many years since I experimented. Craig Brougher, have you had experience with this linkage adjustment?
-- Robbie Rhodes
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(Message sent Fri 16 Aug 1996, 15:53:18 GMT, from time zone GMT-0700.) |
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