[pianotech] Interesting action on Yamaha YUA

[David Ilvedson]

I noticed a leather backing behind the spring rail...

David Ilvedson, RPT
Pacifica, CA  94044

----- Original message ----------------------------------------
From: "Marcel Carey" <mcpianos at hotmail.com>
To: pianotech at ptg.org
Received: 7/6/2009 11:46:17 AM
Subject: Re: [pianotech] Interesting action on Yamaha YUA



>My guess is that it might be noisy. The springs look like they might have a resonant 
>frequency and they might produce their own sound. But this is only my guess. It 
>wouldn't be the first nor the last time I'm wrong. But, metal springs only held at one 
>end is very suspicious to me.

>Marcel Carey


> 
>> Date: Mon, 6 Jul 2009 12:21:18 -0400
>> From: pianoguru at cox.net
>> To: pianotech at ptg.org
>> Subject: Re: [pianotech] Interesting action on Yamaha YUA
>> 
>> ---- Ryan Sowers <tunerryan at gmail.com> wrote: 
>> > A 1983 Yamaha YUA (52" upright) ..... The springs are
>> > flat, about 1/8" wide and do not engage the hammer butt until the hammer is
>> > about 5/8ths or so from the strings.
>> > I'm wondering if anyone else has had any experience with this style of
>> > action?
>> 
>> I have studied the US patent for this action, (#3,946,635) issued 1976. I'm glad 
>to see it was used in production and good reports of its performance. It doesn't 
>appeared that it was used for very long. Does anyone know how long it was used? 
>Or, if and why it was discontinued? 
>> 
>> Frank Emerson

>_________________________________________________________________
>Internet explorer 8 aide à protéger la vie privée.
>http://go.microsoft.com/?linkid=9655573