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Hi -

I have a weird overtone ringing sound on a few notes on my new piano. The fundamental is there, but then there is this weird noise that sounds like one or more overtones going wild above the fundamental. Is this likely a string imperfection, or a voicing issue or what? Only two or three notes have this problem.

Thanks!

Bass or treble?

bass. in the bi chords.

It could even be tuning, but only someone who hears the piano can tell. Ask the tuner about it when it is tuned.

Bass strings are extremely susceptible to false beating. This is probably what is going on. The only way to remedy the problem is to get a new sting or voice the string itself.

David,

Could you give a short indication of what's meant by voicing a string? I wasn't aware that any physical changes can be made on strings (other than perhaps removing kinks, leveling them, etc.)

The Petrof 46” studio upright I owned had an odd ringing overtone in a couple of the bi-cord bass notes. The tuning was right on par. I could lightly needle the strike-point of the hammers and improve the tone, but the ringing overtone never disappeared all together. I was afraid to needle the hammer too much. It was tolerable but annoying.

Rick

This is a new piano. It is bichords. There is an overwhelming possibility it is nothing but bad unisons.

You would stretch the string by lifting it slightly off the bridge. Doing this would equalize all of the segments of the string from the tuning pin to the hitch pin.

But this would only help in rare cases, usually if the string itself is bad you would need to get it replaced.

I've never heard of that kind of "voicing" of a string. It can not equalize tension from the tuning pin, as you are doing nothing on this side of the string. And I doubt it will equalize tension accross the bridge pins, as they are pushing the string against the bride cap and friction is not released when trying to lift the string. Furthermore, this equalizing of tension only helps to tunning stability, not to tone production or ringing overtones.

On the contrary, seating the strings on the bridge, by gently tapping down to the bride cap is always recommended to deal with false beats and other bearing points related problems.

I have a similar problem on my brand new piano. Does it sound like this?
http://www.youtube.com/watch?v=6U1_-w22goY#t=25s

The problem is that a had a piano technician come over and he can't hear what I'm talking about! My friend came over and he can hear it. It's not on a copper bass string though.

Can anyone help me identify that ringing overtone?

Electronblue,

I can hear what you are talking about and IMHO it is a voicing (hammer head) issue.

Look for a tech that makes voicing.

Rickster,

Have you tried the side needling at the shoulders as described by Chuck Behm?

Have your technician make absolutely certain that the strings are level and the hammer hits both strings simultaneously and that the hammers are the right shape before even considering attempting any needling. Doing these fundamentals first takes skill and experience and will very likely make your 'problem' notes become among the best sounding notes on the whole piano and your tech will then have to do the same thing throughout the rest of the piano to even things up and you will have a far superior sounding piano. This happens more often than you might think.
Side needling at right angles to the hammer separates the layers and the hammer will return almost to 'normal' within a few days.

Yes, I have tried the side needling, and have noticed some minute differences/improvement in the tone. I think the best voicing I’ve done, in terms noticeable tone improvement, is the traditional hard stabbing motion on the high shoulders and some very shallow needling on the strike point. To me, the biggest challenge with this is type of needling is supporting the hammers well enough to get in a good hard stab without breaking a shank or damaging a flange pin bushing. I use a small board to support the hammers on my grand actions.

I’ve also learned from experience, as others have said, that hammer to string alignment is vital to a clean, clear tone on each note. Plus, it is amazing how a little needle pricking on the strike point can solve an annoying sizzle, zing or ringing overtone, but not all the time.

I honestly think the skill required for voicing far exceeds that required for tuning. (Not that either is easy).

Rick

Rickster,

Do you think that replacing the strings would eliminate this ringing overtone?

Have you checked to be sure the dampers that are allowing the overtones are seated properly?

Hi Gadzar,

I've sold the Petrof studio upright so I don't know if replacing the bichord bass strings would have helped or not (probably so). The buyer hired an RPT to evaluate the piano before they bought it and neither of them noticed it. The overtones were subtle anyway. I guess I'm a perfectionist and I wish I wasn't!

Take care,

Rick

How would damper seating influence the sound of a string after it is struck by the hammer, i.e. while the note is sounding?

it wouldn't but poor seating on another note could. Unlikely by the description here but not to be ruled out. The test for this is simple and takes but a few seconds.

You could be hearing sympathetic vibrations from another string.