[pianotech] Little Cloth "Mutes"

[Ron Nossaman]

William Monroe wrote:
> Hi Ron(s),
> 
> To revive this a bit, I'm curious, Ron N. how you decided upon location of
> your replacement for the duplex.  Did you just move it to the front of the
> webbing area of the plate, or were you trying to achieve a certain 
> length of
> "duplex" segment?

Del wrote a Journal article some years back on his research 
into what factors produced noisy front duplexes. It's 
primarily a combination of length and bearing angle. I found 
his information to be dead on in practice (thanks Del). So I 
try to make the duplexes as short as I can practically get 
them, and somewhere around 15°-20° counter bearing (enough, 
but not creating rendering problems). The length is more 
critical than the angle. I can usually get down to at most 
30mm lengths, which is nice and quiet at these bearing angles. 
The SD-10 terminator modification I posted a while back made 
the "duplex" length about 10mm, which was also nice and quiet 
at a much lower angle.
Ron N