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Bass String Noise Complaint

  • 1.  Bass String Noise Complaint

    Posted 01-25-2019 07:38
    Yesterday I tuned a 6-month-old Pearl River upright (EU118S). Prior to tuning, the owner said that she heard some sort of buzzing or rattling from one or more of the notes right around the bass/tenor break. I listened and while I did hear something, it didn't sound like any clear buzz/rattle to me - I thought it might just be the bad unisons.

    So I tune it. She listens and still complains of noise at the bass/tenor break. I listen and yes, there was what sounded to me like a little bit of imperfect unison noise (shame on me!). So I work on those four notes around the break (the two lowest tenor notes are wound bicords) and clean up the unisons so that they sound pretty darn good to me. She still hears noise. IMHO, she was not hearing imaginary things, but I think she was also being super critical. She may also have been hearing the difference between the lowest plain-wire tenor note and the first wound strings. I did hear a little more noise that I would expect from a very clean plain-wire tenor unison, but relatively speaking, I would say it was a pretty clean bass string unison. Communication was difficult because she speaks little english. Her piano teacher set up the appointment. So I call the piano teacher (she functioned as a translator) and explained all about my understanding of bass strings and string noise. She seemed to understand my explanation and related it to the piano owner. She seemed happy afterward and even gave me a $$ tip.

    My question here is really that I'm looking for opinions on the nature of bass strings and associated noise. I have found that (at least in the tenor) plain wire strings are seemingly fairly easy to manufacture to consistent specifications - and thus, as long as unisons are the same length and bridge pins are solid, tenor unisons can usually be tuned quite cleanly. Bass strings can be another animal all together. Some will tune nice and clean, while others will not uncommonly have partials that don't line up well and will always have some sort of beat (noise). I tune quite a few Yamaha C3s on the cruise ships - most are 10 to 15 years old and I'd have to say that at least 25% of the wound string unisons can not be tuned cleanly. I have noticed that Young Chang bass strings seem to have a higher propensity of bass string unison noise than some others.

    So why do bass strings make undesirable noises? My guess is that the nature of the copper winding just makes it a bit more difficult to manufacture two strings exactly the same - same mass of copper, same tension on the copper winding, etc.

    Am I missing anything major here? Is my thinking up to par? Please educate me!

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    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida
    terry@farrellpiano.com
    813-684-3505
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  • 2.  RE: Bass String Noise Complaint

    Posted 01-25-2019 09:35
    Terry,

    I have noticed the same. I really think it is due to the SPEED at which these pianos are manufactured. It takes significant skill to make really uniform bass strings. The price point of these things does not accommodate the time and attention required for US to be satisfied, and the target purchaser probably won't notice. And of course, the slightest deviation from ideal along the length of the string is going to become manifest sooner or later.

    Possibly too, these may have been pulled past their elastic limit in the chipping process (again due to speed). Once that happens it's downhill from there.

    That's my .02

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 3.  RE: Bass String Noise Complaint

    Posted 01-25-2019 11:08
    May not be a unison problem. May actually be a buzz or rattle. Try tapping down the windings or adding a twist to the bass strings. Sometimes it's just a loose winding.

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    Geoff Sykes, RPT
    Los Angeles CA
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  • 4.  RE: Bass String Noise Complaint

    Posted 01-25-2019 18:00
    Also poor hammer/string mating can produce weird sounds. Very common on pianos like that I've found.

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 5.  RE: Bass String Noise Complaint

    Posted 01-26-2019 09:11
    Did you check hammer/string mating?  It must be perfect or you will hear it.

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    Jeffrey Gegner
    Tipton IN
    765-860-5900
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  • 6.  RE: Bass String Noise Complaint

    Posted 01-26-2019 09:45
    Edited by Jim Ialeggio 01-26-2019 11:30
    Terry,

    I'm not a string maker...but looking for a physical characteristic that could produce un-tune-able wraps, I would suggest, that the noise is produced when the wraps and core have are not behaving as a single unit. Wraps that are not wound tightly and consistently tight along the entire length, as well as at the difficult to terminate swage  ends of the wrap could reasonably be responsible for all kinds of cacophony. Produced by a neophyte, or at high production levels, with the operator never having seen a piano, I would guess the hardest part would be effective swageing.

    I tuned a horrible 30's Jewitt runt grand this week, that had an entire bass like this...the whole bloody thing...The strings looked to have been replaced at some point. It was impossible to create any unisons in the entire bichord area, and I could not get any steady pitch readings from the unichords.  I get a couple of these pianos every once in a while, and am so grossed out, I turn off site tunings, and hole-up exclusively in the shop for a while to make real instruments.

    String mating in the bass will get you nowhere when a string itself is the problem.

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 7.  RE: Bass String Noise Complaint

    Posted 01-26-2019 12:46
    I was thinking along the same lines. Unfortunately, it is not uncommon for me to find a unichord bass string that beats like an out-of-tune unison. If you are unsure, it might be worth checking out listening to individual strings. If that's the case that is also easy to show the customer that the beating is not due to your poor tuning skill :)

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    Peter Stevenson RPT
    P.S. Piano Service
    Prince George BC
    250-562-5358
    ps@pspianos.com
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  • 8.  RE: Bass String Noise Complaint

    Posted 01-26-2019 12:58
    Have the Pitch Lock clips been an option to clear up bichord bass unisons? I've heard they work well in the bass. I've never used Pitch Lock and would like to know when/if they're effective.

    Richard West








  • 9.  RE: Bass String Noise Complaint

    Posted 01-26-2019 16:24
    Richard,

    I'm glad you brought that up. I forgot to mention it. I have used PitchLocks numerous times to to make untunable bass pairs "manageable". If they are marginally bad and I just want to clear things up a bit I'll put them on the tuning pin side of the agraffe or nut (whatever the case may be, and assuming there is room enough to do so). If they are really bad and respond to nothing else, I will put them on the speaking length side (as shown on Scott's website). Although they do change the character of sound (slightly deadening), they really do work to unify the errant beats. It's really a matter of deciding which bad choice is better.

    In every case thus far, the client has agreed that it is better than before. I let them hear it before and after. If they agree that it's better, it stays.

    Now, on a different note, I have had this kind of  situation improve by adding a riblet down in the appropriate area also. But I don't go there until all other efforts have been exhausted, and I need to have reason to believe that it might actually be a soundboard impedance issue rather than a string issue. Make and model of "piano" has a lot to do with this decision.

    Highly recommend having PitchLocks available for this. It's almost like a "magic trick". Theybareca true pain in the buttinsky to put on (especially when they slip and disappear to who knows where), but worth having around.

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 10.  RE: Bass String Noise Complaint

    Posted 01-28-2019 00:21
    The chapter titled " Peculiarities of Wound Strings" pg. 42 Piano Tone Building 1919 may be of interest.
    -chris

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    Just Looking through the Go-Bars
    chernobieffpiano.com
    grandpianoman@protonmail.com
    Knoxville, TN
    865-986-7720
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