In a message dated 98-03-11 18:49:05 EST, you write: << I have been experimenting with finding 'minimum let off distance', 'minimum back check distance', etc. with mixed results. So rather than continue my trial and error methods to determine abstract notions such as 'minimum' etc, my question to the list is: * What regulation adjustments do you consider important to work on for maximizing upright performance, and * How do you in practice determine the optimum setting for such an adjustment. Appreciate any comments, or suggested reading material etc. on this topic. Regards, John Woodrow Sydney, Australia Specs for regulation is only to get you in the ballpark. If they are available, set it to specs and see by moving them a bit will improve the regulation. Keep in mind the wear and tear on the parts because you will have to modify the regulation along with it. There is no reason to believe one regulation step is the most important. Each step affects another, so look at the regulation as a total concept. For a fast regulation, here is what I do and I can do it without specs. Using samples, go through the lost motion, then letoff, and see if you have plenty of escapement of the jack relationship to the hammer butt felt. If this is not very present, move the hammer rail closer to the strings (you can do this by propping it with a rubber mute) and go through the samples again. When you are satisfied glue and shim the hammer rail. Proceed with lost motion, then letoff, keydip, key level (if they are very uneven, do the leveling first), backchecks, and dampers. Of course, tune, then collect $$$. It is always a good idea to memorize the spec ratios for what most pianos will regulate at. 1/8" for letoff, 5/8" for backchecks, 1 3/4 to 1 7/8" for hammer strike distance, 1/2" keyheight, sharps 3/8" above whites. Once you know these specs, you should be able to regulate any action without the use of written specs. Hope this helps. Dave Peake, RPT Portland, Or
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