Hi, Vince,
If this is an institutional piano that can be moved around (at least somewhat) within the room, then there is actually a huge range of possible (if partial) solutions to this problem.
I think that I might start with making sure that the wall between the rooms does not have any acoustic holes or leakage. This would include things like wall plates for electrical or comms links, light switches, places where the floor is not completely sealed; and/or there is nothing above the wall except “crawl space” for air ducts, wiring and the like. This is all before touching the piano, adding wall, ceiling, or floor treatments.
In what now seems like a previous lifetime, I took an acoustics class with a former director of the acoustics department of Bell Labs. On of our projects was to come up with how to analyze the acoustics in a nominally 12’ square room. Everything was fine, and definitely reasonably predictable as long as we didn’t open a door or a window. However, if a 1” hole were cut in the wall or in the window, all bets were off. The point is that even very “small” leaks can lead to exactly what you are describing.
I hope that this is of some help.
Kind regards.
Horace
Original Message:
Sent: 4/29/2026 3:19:00 PM
From: Steven Rosenthal
Subject: RE: Upright Sound reduction panels
Depending on their level of investment and how long they plan to stay, there are several sound dampening drywall products. One is called QuietRock. One upside to that is that it won't affect the timbre of the piano.
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Steven Rosenthal RPT
Honolulu HI
(808) 521-7129
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Original Message:
Sent: 04-29-2026 14:43
From: Wim Blees
Subject: Upright Sound reduction panels
I don't think there is much you can do to keep the sound from going to the next room. I've heard you can 3" thick styrofoam and the cut it to fit between the post. You also try a thick of some sort and nail it to the back of the piano. Or maybe a combined of both.
But to reduce the sound the most will require the piano player to play softer.
Wim.
Sent from my iPhone
Original Message:
Sent: 4/29/2026 2:31:00 PM
From: Vincent Chambers
Subject: Upright Sound reduction panels
Hi gang:
I need to install some sound reduction panels between the back post of an upright piano (Boston 118).
Different sound panels are used for different things… Some are used for absorbing certain frequencies, but do not offer much in the way of soundproofing, others are soundproofing, but I'm not sure which one would be best in this situation.
It's in a small office. Let's call it 15' x 15', it's used for voice training, and part of the problem was the sound going through the wall to the Neighboring office.
I rotated the piano away from the wall, so it was facing the student, which was ergonomically better for the instructor, and now need to put something in there to reduce the sound further because it's still too loud for the vocalists.
What materials have you used to do this?
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Vincent Chambers
Apollo Piano | Stanford
San Francisco, Chico CA
(530) 924-4469 Mobile; 732-642-1100
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