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Featured on the cover of Feb 2004 PTG journal is a cliplike device put on the right two strings of a unison. According to the article it causes the strings to vibrate at exactly the same pitce. Anyone have expieriences with the device? They are attached to the right two strings of all trichord unisons at about 1/8 inch from the bridge in the speaking length. All three stings are tuned as a unison, but this device is supposed to keep the right two strings in unison longer than without the device.

Yes, I just installed my first set here at the school. The patient is an old Lyon & Healy grand in our secondary piano lab. I'll try and report back, but I probably won't work on this instrument again until the spring.

I did notice that tuning was an adventure! The theory is that you tune each unison from right to left. That way the two linked strings are tuned first, then the third is brought into the mix. The problem is that the clips accentuate the "Virgil" effect; that two strings together will vibrate lower that one vibrating alone. I had to pull the first string about 3-5 cents over to get the two together to end up on pitch. I used a lot of "splitting the unison" technique to get the pitch in the right place. I worry about doing a big pitch adjustment, but time will tell. The trouble I had is that this particular piano is a little jumpy with loose pinning, so delicate control is a little tough. Also, I think it would be easier to slide the little clips on cleaner wire...

Ron Koval
Chicagoland

(by the way, didya see my Verituner review?)

Yes, Ron, I enjoyed your VeriTuner article. I bought mine 2 years ago and pray that Dave Carpenter succeeds wildly with this machine, so I never have to be without one. I sent it in for service some time back, and had to go back to my SAT while it was gone. That was really when I realized how much of a load the VT had taken off me. Going back to the SAT, I was doing adjustments and corrections that I didnt have to do with the VT. Looking forward to meeting Dave at the Nashville convention this year

I just got my copy of the Journal today. the concept sounds pretty good but I wonder
how well it will be accepted. I guess we will have to check it out. I am a little concerned about putting a clip in a string under tension.
What happens to the clip when the string breaks during a tuning or if someone really pounds the piano ? It could be very dangerous I would think.

Have looked into this some.

My comments are:
- Pulling strings together means one string having less sdie bearing on bridge pin, maybe no longer enough
- Uniting two strings, inborn with diff inharmonicity seems counterproductive and may make accurate tuning/listening harder
- Creating a metallic bridge or causeway between two strings of unequal length, again causes me concern due to inharmonicity
- Clipping strings together with uniform tension seems impossible due to bridge-pin placement and string alignment
- And finally, placing some foreign aboject (metallic no less) o speaking length of strings seems rather a slippery trick, that has much potential to bacfire and make ugly undesirable sounds...

But as a Frenchman, it is in my blood to be pessimistic...

Manitou - Pianist - Technician

I agree with Manitou - interesting, but given the above, the extra tuning stability is probably a result of the extra pounding needed to tune the two strings in unison in the first place. Nothing like a few good test blows to make a unison stay.