fun at the piano store!

[Ron Nossaman]

>It was flat in the treble, and uinsons out up and down the keyboard. Two 
>days after the last tech tuned it, I played chromatically and the vast 
>majority of bi, tri unisons were very "wavy".
>
>Terry.


Terry,
A few years back, I got a call from a customer of mine about another tech.
She was prospecting for the best tuning she could get on her old Yamaha
grand (don't remember the model), and thought she'd give someone else a try
to see if I was as good as she could do. She went for the University tech,
and had him come out and tune it. A week later, she called me.

I knew the tech, an RPT that qualified at CTE levels, so I called him to
find out what happened. He had no idea, and had just done what he thought
was his usual good job. I asked him if he had pounded everything in good
and he said "No, it wasn't far off pitch". That was the problem.

Yamahas, for some reason I haven't been able to identify, often have a
specific tuning requirement. When you are setting a string at pitch,
especially pulling it up, you need to whack it a good one one time to make
sure it stays there. They'll often drop over 10 cents (mid tenor - high
treble) when you do this. It seems to be  on a piano to piano basis, rather
than a unison to unison, so if you find it happens anywhere in the piano,
do it through the whole tuning.

This happens in all sorts of pianos, but I find it most often in Yamahas.
The only explanation I've come up with that even remotely makes sense to me
is that you are helping the string render through the bridge with that hard
blow. If there is a lot of friction at the bridge pins, it won't happen, so
it doesn't make much difference a lot of the time, but it will save you a
lot of grief in those pianos where it does happen. On the pianos that will
exhibit this pitch drop on one whack (technical term), but don't get
whacked, the string will render through the bridge anyway. It just takes a
couple of days and happens to different strings at different rates, making
the unisons nasty very quickly. This has absolutely nothing to do with
hammer technique, since the string pitch responds quite normally to pin
movements. That tech I mentioned at the beginning was/is a good tuner, and
the piano almost certainly sounded fine when he left it, or he would have
fixed it before leaving. 

I have not had problems keeping new pianos in tune, other than the usual
general stretching, compacting, and settling stuff, since I discovered this
about the second year I was in business. It helps on a lot of somewhat less
than new pianos too.

I think that a lot of tuning stability problems caused by this are blamed
on other things like loose plate screws and pinblock flange fit. I've
followed way too many other techs on "problem" pianos and left a
dramatically more stable tuning than the last XX guys did by just
addressing this one little thing. This is without tightening the plate
lags, wedging the flange fit, flibbiting the jib-jab, or generating any
smoke. I know I'm in the minority here, but this says something to me. 

For what it's worth,

Ron N