<!doctype html public "-//w3c//dtd html 4.0 transitional//en"> <html> <body bgcolor="#FFFFFF"> What you call setoff, Americans call letoff, and what you call letoff, Americans call drop. I think its best to use the American terminology since the list is so dominated by Yanks. Otherwise.. terms are fine. Striking distance everyone understands as blow. Whoosh :) The specs you give are bad...but not the worst I've seen. 1/8th letoff is about 3 mm, and is definantly on the long side, as is drop. Check is gettin down there for sure. How do you know that these are factory specs tho ? Is this a brand new instrument fresh out of the box ? Could be just that it needs a rather standard dealer prep eh ? For standard specs.. I like 1.5 -2 mm letoff, that much again for drop, and 10-12 mm check. I like a firm rise in hammers after check.. but not hopping, and it shouldnt be very noticlble at the key front by the finger. Key dip ends up being a function of blow distance, and I use 10mm as a standard and adjust blow to fit. If I want to get more persnikity about things...then I have to use a bunch more time then what a standard seat of the pants time regulation allows for. Getting a Petrof to do well in a true concert situation is another matter tho. And if you look close enough at a Petrof action you will most often find that the degree it  deviates from standard regulation specs is the least of your worries. Cheers RicB Michael Gamble wrote: <blockquote TYPE=CITE><style></style> Hello all. This is an attempt to get some input from those who (that means all of you I guess) frequently regulate grand actions. From the start we have a few hurdles to get over and of these the principal one is that of terminology. In regulation you get a) the parts which are being regulated and b) the name given to that part of the regulation process. Are we at one with the name "striking distance"? which should be about 1 7/8" Then we have "Set-off" In this part we adjust the "Set-off Button" until it touches the toe of the "Jack" and causes the hammer to stop rising and go into the "escapement" mode.This Set-off happens about 1/16" below the string. Next we have the "Let-off" (I think that's sometime called "Drop") when the hammer after hitting the string is allowed to subside another 1/16". Not to be confused with "Check" when the hammer after hitting the string more forcibly rebounds into the loving grasp of its check-block. If then, whilst the hammer is captivated in check you gradually release the key the hammer should float upwards - not too fast. This we call "Hammer rise".. OK?The point of all this is I went to tune a new Petrof grand the other day and was amazed by how much this Czechoslovakian manufacturer had deviated from what I considered the "norm". The results were as follows:Striking height 1 7/8" (OK)Check 13/16" ?Set-off 1/8"!!!Let-off 3/8"!!!!And the hammer-rise test showed that all the hammers came up faster than you can say knife!Here's the question therefore -What are the correct settings?My Steinway service manual adheres pretty firmly to my first list of requirements except that the "Let-off" is considered with relationship to the diameter of the string affected.Oh yes - there's another aspect of regulation. It's vital that the "Key depth" be correct. Steinway recommend 9.75 on models S - B and 9.75mm on C & DReblitz, on the other hand, is a bit more "global" in his approach giving more latitude.At the end of the day does the piano react as a concert pianist would expect?Over to you.Michael G (UK)</blockquote> -- Richard Brekne RPT, N.P.T.F. UiB, Bergen, Norway <A HREF="mailto:rbrekne@broadpark.no">mailto:rbrekne@broadpark.no</A> <A HREF="http://home.broadpark.no/~rbrekne/ricmain.html">http://home.broadpark.no/~rbrekne/ricmain.html</A> <A HREF="http://www.hf.uib.no/grieg/personer/cv_RB.html">http://www.hf.uib.no/grieg/personer/cv_RB.html</A>   </body> </html>