Had a stability problem today. An U3 was moved to the venue yesterday, and I tuned it today. I tried very deliberately to set the pins, and I did succeed - in all but one section of the piano.

The section starting from the break at D5 and ending with the next plate brace was very hard to tune, the pins felt easy and "jelly-like". Indeed, this was the section of the piano that didn't hold when the McCoy-style banging piano player got his hands on it. Had to correct pretty much all the unisons in that section during intermission.

Could this be due to the pressure bar not being tight enough, or something like that? Seems funny that all those pins in the very same section would suddenly have become to loose. I didn't have the time to play with the pressure bar in the short intermission, but if any of you more experienced techs out there would give me a hint as to what might be the cause of the unstability, I will know where to look tomorrow (I tune the same U3 for tomorrow nights gig.)

You should probably take a pin setter and tap the pins in this section before you start the tuning. Tightening the pressure bar isn't going to change the "jelly" like feel to the pins. It is also pretty unlikely that a Yamaha would have the pressure bar set at the wrong height. Yamaha has very good quality control. It is very unusual to find one that wasn't set up to factory specs in the first place.

ok, i will, thanks for the reply!

Thomson,

that was indeed the case, instant help by the tapping. I would have done that yesterday, too, but I was unsure as to wether a such clearly defined problen in a very specific section between the plate braces would be due to some other problem.

Thank you for your help, will go to the concert now and hopefully experience stability!

I'm glad that helped. There is nothing worse than sitting through a concert and hearing your tuning being demolished. I have trouble enjoying a concert when I have tuned the piano because I have my tuner ears on through the whole thing. I don't listen intently for drifting unisons if someone else has tuned the piano.

Same here... wouldn´t think twice about it when I play myself, but it´s a whole different story at the tuner seat... good concert, though, and even better - that problem area held up through the night - thanks again