Why do the low notes on my piano have a high dissonant metallic overtone?

Question

Whenever I hit any of the notes on my piano (it's a Bergmann grand, not full size) from G2 down to A1, if I have my finger on the string (or strings) and hold the note down, I hear a very harsh, high, dissonant tone. When I release the key, and the damper goes back down, the tone goes away.

I just had my piano tuned by a professional and it didn't fix it. I hear it all the time when I'm playing the piano, behind the actual tones for the keys I'm pressing. It's quite irritating because the "overtones" are very apparent (to me, anyways).

I'm hoping some people who are knowledgeable with pianos or music in general can tell me: What is causing this, and how I might go about fixing it? 10 points to the person with the most useful information...

Answer 1

to add onto Glinzek's good answer:



If you have a decent piano tuner (an RPT or member of the PTG, then they probably are good) then it's probably a technical issue with the piano.



What happens is that with low notes most of the overtones that make up the pitch you hear are audible. When you get past the 15th partial these overtones are audibly dissonant (you start getting microtones that aren't part of our 12 chromatic pitches). For mathematical reasons the problem is proportionally larger as the string length gets shorter, so for small grands, that means you have less margin of error both for making the bass string, and tuning it to solve the problem.



The problem can also be worse with the wound bass strings in cheaper instruments, because if both strings are not exactly the same, then the overtones of on may be slightly stretched, or compressed, as compared to the other bass string. Meaning for the left string the 15th overtone is a few cents off from the 15th overtone of the right string for the same pitch, even when the fundamentals are exactly the same. If that's the case then the only solution is new bass strings.



Many budget pianos suffer from this problem. It's cheaper to make bass strings in bulk, without careful consideration of the specifics of the piano they go into. The fancier more expensive pianos tend to have bass strings custom made for each piano.

Answer 2

There might be a problem with the strings themselves. Try holding down the sustain pedal and plucking the strings with something like a nail file. Do you still hear that nasty tone when the string is plucked? If you do, then the problem is in the string. Maybe something was spilled on the strings?



A common problem I came across with pianos was that the copper winding around the string would come a little loose over the years. When this happened, you would hear a nasty sound. In these cases, I would take the string off, twist it a couple times, and put it back on. By twisting the string this way, I've tightened the copper winding.



Call your piano technician and have him/her check for any spills on the strings. Also ask if the strings need to be twisted. If he/she doesn't know what that means, hire someone else.



BTW, NEVER touch the bass strings with your hands. The oils on your skin are terrible for the copper and will ruin the strings.

Answer 3

On shorter pianos (Bergmann makes a 5 footer and a 5'2", as well as a 5'9 and 6'1), the overtones in the bass will be more audible than on longer pianos. This is particularly true of the more budget-oriented pianos, of which Bergmann is one (it is Young Chang's Chinese-made instrument). They are good pianos given their price range, but when you go budget, you do sacrifice quality and refinement.



The possible solutions? New bass strings perhaps -- a somewhat expensive proposition, but cheaper then buying a new, larger piano. But there is no guarantee that it would solve the issue. I have heard of some technicians who applied vaseline to strings to curb their "wildness" -- I don't recommend it.



Did you talk to you tuner about the problem and what it might be? Simply tuning a piano would not correct something like that, but possible even make it more audible. Have you gone to the dealer and played similar models to see of you can hear the same thing? Have you contacted the dealer or Young Chang to see if this could possibly be a warranty issue? MAke some noise about it -- Bergmann has a 10 year warranty to the original owner.



You may end up having to live with it until you can upgrade.



Best of luck



G.

Answer 4

Bad duplex scale design or missing stringing braid on the lower notes (below the top octave and a half or two.)



Your tuner should be able to make suggestions for remediation.

Answer 5

you have your fingers on the strings? maybe it is a harmonic....



why would you have your fingers on the strings?