I am thinking to buy used Yamaha G2(1998). The shop owner said it got 'A' grade from JUPA.
The external and internal staus were very good and sound was mellow but not too weak.
I brought muting rubber and check every single string to check id there is any false beat
Most of strings were ok but there were around 10 strings had false beat. 7 strings mild and 3 strings
made some annoying vibrations.

Shop owner brought technician and he said it's quite common for acoustic pianos , even high end brands like Steinway and Bechstein. It's almost impossible to fix.

Other technician tapped the bridge pins with small rubber hammer but nothing changed. Shopowner
said he will try to fix them if possible.

If I play fast tempo music , I hardly noticed the false beat but it makes me distracted when I play slow tempo music.

Is it almost impossible to fix? I sold Yamaha U3 as I asked tuner fix them and he said it's easy
to fix but it happend again after 1 week he did something.
Then he said it needs to be rebuild.

Most people don't mind about false beats?

Tony,

"False" beats are very common. They are largely produced by.slightly loose bridge pins (loose at the top of the hole), though not universally. A skilled tuner can mitigate SOME of these in the tuning process, but not all. CA glue is another treatment but I am NOT recommending it to you. Sounds to me like it's not that big of a problem on your piano.

Peter Grey Piano Doctor

Thank you Peter, is it possible to remove the false beat perfectly?

What's JUPA?

Japan Used Piano Association

If you listen to something closely enough, you can always find things which are wrong.

I had a client with a M&H BB that had many false beating wires especially from upper tenor to the top.
I tried several times to point them out to him and he just could not hear them.
The piano was very difficult to tune but he always liked it and the false beating was never an issue for anyone but me.

I've had many, many Bechsteins like this. I've come to the conclusion that the beats enhance the sound for those that can't hear them as beats.....rather like chorus is used.
Nick

A well known tech got rid of most of the "false" beats in a client's piano, mostly because it drove him nuts trying to tune it, so he convinced the client to go through an entire CA adhesive regimen to solidify the bridge pins. It worked! Only problem was that the client DID NOT like the sound of the piano as a result...in fact neither did the tech. There was a character there before that was now GONE.

He published this scenario on another forum. Very interesting.

Peter Grey Piano Doctor

A quick way of testing if a false beat is caused by a loose bridge pin is this one that I learned from Roger Jolly in Canada:

Gently rest a heavy duty screwdriver against the bridge pin, pressing sideways, being careful not to press so hard that you widen the hole and make things worse. And don't touch the string. Just the mass of the screwdriver resting firmly against the end of the pin is all that is needed to stop the bridge pin from moving in the bridge. Play the note with only this one string sounding. If the false beat goes away, you know it is a loose bridge pin. If not, it is something else. Most of the time it will be a loose bridge pin.

Yeah, but on the BB I serviced mentioned above, this was not the case, bridge pins were in solid.
I believe there was either an impedance mismatch between string energy and soundboard assembly or the bridge pins were made of a softer more flexible material possibly stainless steel.

Interesting indeed.