Improve Piano Sound: How to Slow Down Dampers for a Cleaner Performance

[fohman]

Hello all,

I am a live sound engineer looking for a creative way to slow down the dampers on a grand piano as the pedal is released. When the piano pedal is depressed, the dampers lift off of the strings, and when the pedal is released, the dampers come back down on the strings to mute them. The problem is that when the dampers land on the strings, a thumping sound is made which is picked up by nearby microphones. The thump is mostly present when the pedal is released quickly, and not nearly as present when the release is gradual and slow. I need to come up with some device which can be quickly and easily mounted to the piano that will slow down the dampers just before they land on the strings, much like a jumper pulling a parachute before landing. Probably the easiest piece on the piano to manipulate would be the vertical rod which the pedal pushes on. It's range of motion is about 1/2" up and down. There is also a wooden lever which the rod pushes, but it might not be easily accessible on all pianos (this device needs to be portable and fitted to all grand pianos). The pedal itself may be hard to manipulate because it must be played and there is often very little room between it and the ground, and the dampers themselves are out of the question as most musicians would freak out at the sight of any foreign objects placed inside their piano aside from microphones. Any ideas?
Thanks!

 

[Bystander]

Google "trunk strut/hatch strut/universal lift support;" fit a clamp to the "pedal rod" on both ends.

 

[fohman]

That's a great idea! Do you think there is a small one which allows free motion except for at the very end of the cycle, probably 1/8" or less of restricted motion right at the end of a 1/2" total motion?

 

[fohman]

A friend suggested using a foam block that is dense only on one end... as the pedal comes down to rest on the foam, it's rate of deceleration increases as it compresses the more dense areas near the end. See any merit to this?

 

[Bystander]

foam block

Duh . That's even better ---- less mechanical opportunity for failure.

 

[fohman]

what about those things that cause cupboards and drawers to close slowly at the end instead of slamming shut? anybody know what they are called, or where to buy them?

 

[billy_joule]

'Soft close', there may be other names. Most hardware stores will have them.
https://www.softclose.com/
http://www.homedepot.com/p/Liberty-LH-Cab-Door-Soft-Close-Damper-790104/203299689

Have you tried asking on recording forums? I'd guess this problem has existed since recording instruments has, there may be some special trick out there. Otherwise, foam is a good option, easy to adapt to different pianos, just cut to size.