Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Undamped resonance on M&H BB

When I play B4 I get a huge resonance on F#6 which is the first undamped note. ( There is a tiny resonance on G6 when C5 is played but not at all annoying, and no other annoying excitation of undamped strings above G6. ) It makes B4 stick out as if it was improperly voiced, but if I dampen F#6 when playing B4, B4 sounds the same as the surrounding notes. Any ideas to reduce the energy transfer?

Do not know that piano but check backscales in low mediums and basses, where the lenght allow to have such notes sounding.
Sometime very active. In need of more tight ribbon.

Thanks Isaac. I have checked and they are quiet.

It's a feature! 'Enjoy!

Thanks a lot! I was hoping for a "how to install your own extra damper on a new grand" tutorial.

Soundboard resonance? If so could it's frequency be changed with weights or riblets? What do M&H say?

I am confused. If I very gently dampen F#6, using a felt mute laid horizonally on the three strings, the sound of B4 matches the sound of the surrounding notes. If I undampen F6, or E6 and play A#4 or A4, I get the same sound as B4. It seems to me that M&H could have added another damper to the rail. There is room.

Put a clean glove on. Play the note, and then damp the strings from the bass to the treble with your gloved hand. I bet you will find that there is a damper leak on one of the bass notes.

+1

1 +1 +1 = Three. I'm convinced there is a leaking damper.

I have worked on a number of "BB"s and there are plenty of dampers.

We're all guessing without seeing the piano, and some of the suggestions are good if you exclude my attempt at humor. The best course is to have a good tech actually look at, and listen to, the piano. There is just no substitute to being right in the same room as the piano, and occasionally the problem is something that is way out of the ordinary. Eyes and ears work much better than a computer monitor.

I checked the piano several times using BDB's suggestion. Sadly, no leaks were found. I checked as well using a plectrum and could detect no damper bleed. That would have been an easy fix. The backscales are quiet as well.

Thanks all for your suggestions.

C'mon, guys, it's extremely rare to find such resonance so high in a pianos scale but it does happen. I would trust Mwm's assessment of the situation (read his opening post a little more carefully, please.

I have fitted extra dampers in a situation like this, in fact, Yamaha produced a kit for their uprights with this problem so at least one manufacturer recognises it.

I once saw a situation where a tech, apparently years ago, put a small piece of black felt under the strings on the bridge. Hardly visible. I assumed it was for this or a similar reason. When I saw it there was no evidence of this problem but soundboards lose their resonance there over time anyway so I have no idea how effective it was originally.

I dont remember the configuration of this model even though I did work for a prolific M&H dealer 30 years ago but If there is room without extensive modification to the tray, guide rail or sostenuto, etc. the solution would be an extra damper.

Moving the piano, even slightly can ameliorate the situation but not often.

P. S. there is an extremely filthy factory trick for this that takes seconds and is very effective. An intelligent tech who knows the rules will tumble on it eventually with a little thought, you got to know the rules before you can break em... but I'm not going to be guilty of disseminating this stuff on a public forum.

Have you tried damping F#6 with your hand to see that the sound actually comes from those strings?

Read the opening post again. (again)