Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Weird overtone ringing on a few notes

Ah, OK, hadn't thought of it that way. I wouldn't have thought that sympathetic vibrations can actually be so strong as to stand out over the note while it's being played, but only become really audible after it's released. Learned something new - thanks!

Well, think of a guitar. When you play a harmonic you are only very lightly touching the string in a particular location and that note is plenty loud. In fact was used very effectively on a song from the 70's called Roundabout. This same phenomenon can occur on a piano as well.

I knew there would be some Steve Howe fans around here……….
Here is the intro John is referring to……

http://www.youtube.com/watch?v=2u5_7yg8O_g

very nice Dan! Thanks for sharing. SM

I finally got around to checking out this thread, and I'm surprised that nobody has suggested a longitudinal wave as being the culprit. They stand out as a gong like tone that no amount of needling or tuning will have an effect on - in fact one way to isolate it is to tune the string flat and sharp: you will hear the pitch of the string change but the pitch of the longitudinal wave will not.

I had a client with a new Yamaha C-1 that had a strong longitudinal wave coming off D2 bichord, and it was driving him crazy. We replaced the strings and the replacement strings had more wrap on it - it came scarily close to the agraff, but the client is much happier with the sound.

I had a client with a Bosendorfer that had a similar problem. I had one of Seattle's top technicians consult with me on it and he's who clued me into this phenomenon. Once you become aware of it you start noticing it on a lot of pianos, but sometimes it can really stand out. My understanding is that its pitch is defined by the length of the string not the tension, and that the vibration travels lengthwise along the string, not transversely.

If tuning and voicing doesn't fix your problem, you'll have to try replacing the strings. If the new strings have the same problem it may be a scaling problem that will require a different wrap/core wire configuration.

Being a string player, I know about flageolet tones, and use them myself (amongst others, for cross-checking tuning).

Now coming back to this thread: if the damper of the OP's piano were touching the string while it vibrates, causing a quasi-flageolet, would that not be a damper lift problem, rather than a damper seating problem? That's where my original question to SM originated from.

That depends. Sometimes the damper felt itself needs replacing and so "leaks." Or sometimes the damper gets bent and so doesn't hit both (or all three) strings correctly. In either case this could cause harmonic tones. Sometimes the dampers were not adjusted correctly in the piano's initial setup from either the manufacturer or original dealer.

Eventually damper felt needs to be replaced as it stops being effective. This would not be the case on a new piano I shouldn't think unless someone had got in there and started spraying chemicals/oils/wd40 around.

Hey everyone. Thanks so much for your responses. I am still in the process of trying to figure out what my problem is. I just had the piano tuned. The notes sound much better, but the problem is still there. I guess the next step is to have a voicing specialist (or a tech who is good at voicing) out to look at the hammers, dampers, and how the strings are sitting (whether they are level, etc).

Electron Blue, the problem that I have sounds similar to the recording that you posted in that my notes and your recording sound to me like there is extra ringing / beating in one or more overtones above the fundamental. Your recording sounds a little bit different than mine though. If I can, I will make a recording of my own notes and post it. I wonder if I would need a high quality mic to capture the sound sufficiently for people to really hear it...

simple test to demonstrate harmonics: Hit any note while silently depressing the octave above note, the octave above will ring. You can repeat this test by depressing the harmonic sequence that follows for that note, add octaves, 5ths, 3rds, etc.