Yamaha U1 - spongy, lack of repetition...

[Keith Roberts]

> Regulation looks good, very good & uniform.  There is only slight excess
> lost motion.
>
> The symptons get better with left pedal depressed.

You said it right there. The hammer rail felt has packed and the hammers
have grooved and the rail has settled so the strike distance needs to be
set. That's the first thing to check. When that's adjusted you'll find
there's way to much lost motion which is what you would expect in a newer
piano that hadn't been regulated. Then check the key dip and raise the
balance rail if necessary. Does the U1 have that adjustment?
Measure the strike distance from the back of the hammer to the string then
push the hammer forward to the string and repeat and subtract.

Keith R