Pianotech

Hi. The piano is a Yamaha U1. I've glued hammer 84 (G#7) onto a new shank into a new hammer butt because the original hammer butt broke. This hammer assembly resonates at D#5. I've determined this by pressing the flange firmly against a table or the side of any piano and thumping the back of the hammer. When I place the assembly in the U1 and tighten it up, the piano resonates the D#5 very loudly when playing with the key or when simply thumped on the back of the hammer without it even hitting the strings. Other hammers in that range also resonate pitches that are audible as pitches, but higher than D#5, and the piano doesn't seem to resonate those higher pitches as loudly. I've reglued the hammer with different shanks and a different hammer butt hoping the pitch of the assembly would change, but it is a solid ringing D#5 every time. Pressing the flange into the side of the piano and thumping the hammer produces a loud D#5. Putting the assembly into a different U1 and thumping the back of the hammer produces a D#5. Any ideas on how to change the pitch of that hammer and shank, or how to damp the vibration? Thanks.

Jonathan,

Very odd indeed. If I were faced with this I would try clipping a mini binder clip to the shank in various places to see if that changes it at all.  I'll assume you've checked and rechecked all the action bolt mountings bottom and top, and ruled out the hammer rest rail (that's a common source of stuff like this), etc.

A question needs to be asked though...is this D#5 audible to the owner, particularly when the front board is installed? Or any of the other errant pitches emanating?  Or, is this just something that bothers YOU?  😉 

Peter Grey Piano Doctor 

Thanks, Peter. I've checked the action bolt mountings, not the rest rail. Will check that. I've experimented with weighting down the the base of the shank, and it does lower the pitch of the hammer. I've not tried this in the piano to see if it lowers the pitch below what the piano is wanting to resonate. Since posting this I've glued the hammer again with a different shank and hammer butt and the pitch has dropped by a half step to D5. Haven't tried it in the piano yet.

The owner is not around. This is a church with a lot of pianos, and they just let me in to do my thing. The music director is quite capable and could no doubt hear this. If it were an old beat up spinet, I would just let it go, but this is a relative nice piano. It's quite loud. When I play a chord that doesn't have D#5 in it, it sounds like someone is playing a D#5.

Yamaha support's best guess is solve the problem by changing the pitch of the hammer by adding or removing material. Thanks!