Hi David,
Yes, several densities are available, in different thicknesses.
I have a fairly dense red felt , its specific gravity is 0.36 - 0.40. (This is the kind of felt used as understring felt)
I have Crescendo felt, it is softer and more resilient, the specific gravity on that is about 0.32. This only comes in off-white.
Then there is the softer red felt, which I suggest for damper tray felt etc. Specific gravity of 0.20
I think that with careful regulation, especially of the damper up-stop, the bounce back of the underlever on the key can be minimized or eliminated.
As well, to add to this conversation, I received a personal email about this thread, reminding us that ideally, the felt should not be glued below the area of impact, on both the tray felt and the key end felt. This also helps to reduce noise.
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Jurgen Goering
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Original Message:
Sent: 06-16-2018 08:09
From: David Skolnik
Subject: Damper tray felt
Hi Jurgen -
In my admittedly non-player perception, the impact of the returning damper lever on the overly firm keyend felt can be quite noticeable. I'd be interested if you have something somewhat less firm than what's generally around. If you have a couple (or more) possibilities, I'd try some.
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David Skolnik
Hastings-on-Hudson NY
914-231-7565
Original Message:
Sent: 06-16-2018 02:56
From: Jurgen Goering
Subject: Damper tray felt
My feeling has always been that dense damper tray felt is prone to producing a thumping noise, as all 68 (or whatever) underlevers are struck and lifted at the same time. Key end felt/damper lift felt, on the other hand, can be a bit firmer. This helps the stability of regulations and I have yet to hear pronounced noise originating from that interface.
More and more technicians are approaching me (at Piano Forte Supply) with special requests regarding dimensions and density of felt strips, and I am glad to say I can usually accommodate these requests because I stockpile a considerable variety of different felts.
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Jurgen Goering
Original Message:
Sent: 06-01-2018 15:40
From: Zeno Wood
Subject: Damper tray felt
Happy friday!
I notice that Steinway damper tray felt is much wider, thicker, and denser than the stuff sold by Pianotek. Any thoughts on comparative advantages or disadvantages?
Thanks!
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Zeno Wood
Brooklyn, NY
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