Hi Mike et al., Thanks for the feedback. I removed the muting from tenor section and... WHOA!... It didn't sound all that much different. <grin> If anything, I might have squeezed just a bit more power and sustain out of that section, but the difference hardly seems noticeable. I couldn't tell much difference in the tone. I'm wondering if the relative lack of sound contribution from the duplex scale in my piano has something to do with the lack of tuning. (I would think the tuning of the duplex would have to be pretty close to some harmonic in order for the strings to become excited by the vibrations in the speaking lengths.) Reblitz says that most piano manufacturers recommend the duplex not be perfectly tuned, so that the higher harmonics will not be too harsh. (Perhaps they say this because they don't want to tune the duplex???) I get the impression from you folks that the duplex really *should* be tuned. Does this mean *exactly*, within a certain cent range, or systematically off by so many cents? This begs the question of how one does tune the duplex scale. A wire will hold its place around a hitch pin from the friction, provided the tension differential is not too great. How about slippage through the bridge pins? I noticed when repositioning an improperly installed wire over the aliquot plate (requiring me to loosen the string) that the duplex was way out of tune. In order to retune it, I had to overtension the wire by about 1/2 step to get enough slippage through the bridge pins and then release tension from there. Are small differences in tension on either side of the bridge stable? Or would vibration in the string have eventually caused the string to slip, the duplex segment to increase in tension, and the main speaking length to go flat? Of course the only way to make major adjustments in the tuning of the duplex would be to shift the aliquot plates. Do they slide? How does one go about bumping/sliding them? Does one give a tap in one spot, move over, tap again, move over, tap again, etc., etc.? Can they be fractured in the process? Does one release string tension first? If so, I presume it is necessary first to calculate an adjustment in aliquot plate position, rather than moving it until it "tunes up." If nothing else, loosening the tuning pins results in a tension differential on either side of the bridge. Regarding my duplex segments that are tuned to sevenths, I don't think there is enough adjustment room to bring them up to even octaves. I think they were designed to sound at sevenths. Again, I think these duplex segments were designed to be excited by the *adjacent* unisons. (Surely this is possible, since the sounding of one note causes many strings to ring sympathetically throughout the entire piano.) I don't think I would need to do much adjusting. The duplex segments are very roughly (+/- 15 cents) in tune with *some* note, for the most part. I can see where the end of one plate might be moved a mm or two towards the bridge to bring those duplex segments up to pitch. If this is a worthwhile endeavor (especially considering that I will also be restringing the tenor and treble with more correct wire sizes than the .041 some previous technician seemed to love), how much in-tune or out-of-tune should the duplex be? When I pull up the new strings, I presume I should overtension slightly (about 1 half step??) to bring the duplex up to pitch and then release tension. Correct? I would think that if I didn't do this, the bridge would end up with a considerable lateral force on it in the direction of the pin block. Correct??? And yes... I will be working a couple of unisons at a time... but I still want to be cautious. Any advice is appreciated. Thanks, Sarah ----- Original Message ----- From: "Mike and Jane Spalding" <mjbkspal@execpc.com> To: "Sarah Fox" <sarah@gendernet.org>; "Pianotech" <pianotech@ptg.org> Sent: Wednesday, November 13, 2002 8:55 AM Subject: Re: S&S D Duplex Sarah, Regarding tuning of the duplex: Others with more experience may chime in here, but it seems unlikely to me that the duplexes were designed to be tuned to sevenths. The few tuned duplexes I have taken the time to observe, were tuned to unisons, fifths, octaves, 12ths, etc. I think these intervals would be more likely to make pleasing sounds, because each string and its duplex would have lower coincident partials (i.e. partials in the human audible range) than, say, a 7th, 6th, or 3rd. So if you have room to move the aliquots a little towards the hitch pins and turn those sevenths into octaves, try it and let us know if/how the sound changes. Mike ----- Original Message ----- From: Sarah Fox <sarah@gendernet.org> To: Pianotech <pianotech@ptg.org> Sent: Tuesday, November 12, 2002 10:15 PM Subject: Re: S&S D Duplex > Hi Paul, > > I have the exact same question regarding my '33 Wissner concert, which is > very similar to the D. There's a braid through the duplex from notes 36 > through 52 but not in the upper range. My guess is that the prior owner > and/or his tech thought the duplex sound was too harsh, perhaps in part > because the hammers (to be replaced soon) were/are hard as mallets. > > I was also wondering about the tuning of the duplex scale in that note range > (the muted range). Most of the duplex segments are tuned to sevenths, which > I figure are intended to resonate with the next lowest unisons. Is this > normal? The treble duplex is mostly octaves, which makes more sense to me. > Is that how the D's duplex is tuned? > > Thanks for any advice from the list! > > Peace, > Sarah > > ----- Original Message ----- > From: "Paul Chick (EarthLink)" <tune4@earthlink.net> > To: <pianotech@ptg.org> > Sent: Tuesday, November 12, 2002 8:48 PM > Subject: S&S D Duplex > > > > List Members: > > The piano is a 70's S&S D, teflon throughout, with string braid run > through > > the duplex scales behind the bridge, in front of the alequates up into the > > sixth octave. I pulled one piece out from the high end as the customer > > played the piano. His immediate response was how much cleaner and more > > powerful the fifth and sixth octave sounded. He did not want the rest of > > the braid removed "until I get use to the new sound." He states that the > > string braid has been in the piano since he purchased it. It was sold to > > him as new. It's been 2 years since that time. Now he wants new hammers, > > etc. I intend to remove the braid and voice the new hammers accordingly. > > Can anyone explain why the duplexes were muted; am I heading for more > > trouble than I care to deal with? Any suggestions/comments will be > > appreciated. > > > > Paul Chick > > > > _______________________________________________ > > pianotech list info: https://www.moypiano.com/resources/#archives > > > > _______________________________________________ > pianotech list info: https://www.moypiano.com/resources/#archives >
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