Hi Richard, It is my thinking that unless the strings are seated on the bridge (setteled in ) That the test blow will partially settle the string. In pitch raises of over 25c I go to work in seating the strings as if it were a new piano to remove the elastic curve arround the bearing points. This I call a pitch stabilization process. There is usually a drop in pitch of 15c to 30c as the string is seated at the bridge and 15c at the pin bearing points. On a new piano that is flat I always shoot for too high and know that the seating process will bring the pitch down for me. With older pianos it is always a guess so the first time seating is not done untill the return visit. At which time if the piano is close to pitch the bridge is set and on the next service the capo area or agraff with full leveling on grands. BTW Hope to have my new pocket level ( have carried the proto type in my pocket sans case for a year without damage to the vial) somtime this summer Joe Goss > I have always supposed the main reason a test blow will flatten a string > is because the pin is not seated, or "set".
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