I frequently replace vintage Steinway back actions with Renner's current iteration. However, we all know that the sostenuto tabs are 3 to 4 mm longer, meaning they extend toward the proximal side, and can create some problems in regulating the sostenuto rod..
The remedies involve either relocating the pivot pins on the tray or on the blocks, or removing material from the back of the block to move the tray to the distal side. This can create some other problems. It can change the vertical alignment of the damper wire slightly. It can lengthen the contact point of the damper lever increasing the touch weight of the damper lever itself. Other than using somebody else's product, like Tokiwa, I've never really come up with a satisfying solution. I'm wondering if anyone else has.
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David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
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