Why does a string go out of tune? There are many reasons. It does NOT necessarily mean there is something wrong with your technique. Some pianos just simply have better unison stability than others, and all the various reasons for this could fill a book. I won't try to list them all here. For what it's worth: Friction is very high between strings and bridge pins. I have made measurements that indicate that it is necessary to change the pitch of the speaking length of a string by 50 to 100 cents before it will move at the bridge. This means that no matter how hard you pound, you will NOT equalize the tension between speaking lengths and string tails. You will break something before you can pound hard enough to do that. What you WILL do is cause it to move if it is about ready to move anyway. The side bearing angle of the strings at the bridge pins has a big effect on this. I did demonstrations showing these effects at the conventions in Kansas City and Albuquerque, and several state conferences before that. I'm sorry, but I can't give you a quick fix for the problem. What I can tell you is that beating the stuffings out of the piano won't eliminate the problem. Sincerely, Jim Ellis
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