[pianotech] Yamaha Uprights

[Ron Nossaman]

On 12/1/2012 10:50 AM, George Bartlett wrote:
> Hi Folks,
> Does anyone have any info on the cause of Yamaha Upright double striking
> on soft playing.
> George

How old a piano?

Back when I was doing dealer tuning on new Yamahas. this was very 
common, and always the same thing. The new owner, being unfamiliar with 
the piano, and/or new to music lessons, just wasn't completing the 
stroke. As they depressed the key, they would feel the damper pick up. 
Then, as they felt the additional resistance at the beginning of letoff 
as the jack tail contacted the letoff button, they'd let up and not push 
through letoff. The jack would then not clear the butt, and double 
striking was the guaranteed result. Once they were made aware of it and 
learned to complete the stroke to the bottom, the problem always 
magically disappeared.

You can screw up the action by weakening damper and jack springs and 
widening letoff to accommodate, but the best fix is teaching them how to 
work the action.

That's with a new or fairly new piano. If it's an older instrument 
that's badly out of regulation, start with that.
Ron N