Cy I got to thinking about this and thought I'd mention another advantage to using this setup. By using both front (of capstan) and back magnet pairs one is able to achieve 25 - 30 grams of force without really changing the coupling between whippen and key. If you tried to do this with whippen assist springs you'd have at least half the whippens floating in the air above the capstan. But since the back manget pair are pulling the key and whippen apart about as much as the front pair are pushing apart... the net change in the coupling is about Zero, whilst the net change in Balance Weight is large. This may seem a bit confusing, until you install the magnets as per my instructions in an action model yourself. But if you run the leverage numbers it all comes out right and makes perfect sense. Now as to the desireability of using such amounts of counter balancing force. Thats another question entirely. One thing it allows for is the widest spread between hammer inertia and key inertia possible. Should it be shown at some time that high hammer inertia and low key inertia is a good thing... then this is a great way to accomplish that. Another thing is that because you can use this much force without lifting the whippen away from the capstan.... you stand free to design different FW and SW curve combinations then have previously been readily available. One example might be a constant key inertia over the whole key bed. Say 10 grams of Frontweight, placed at the middle of the key, a SW curve that moved from about 11 grams in the bass to 6 in the treble. Magnets adjusted / installed to yield an even Balance Weight. Whatever else this might accomplish, it would have a strong tendency to create a very even dynamic touch, with even and very light key inertia and slight tailing off of hammer inertai. Lots of configurations become very readily available when it comes down to it. Cheers RicB Richard Brekne wrote: > Hi Cy, and Dale > > The advantages are ease of adjustment and cost of installation. > Further it doesnt work by employing any force external to the action > itself. > -- Richard Brekne RPT, N.P.T.F. UiB, Bergen, Norway mailto:rbrekne@broadpark.no http://home.broadpark.no/~rbrekne/ricmain.html http://www.hf.uib.no/grieg/personer/cv_RB.html
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