>...What differences there may be would be so >small that it would not be discernable. I predicted the same before Virgil >and I went after it. Then, there would always be the arguments that, it >wasn't the machine, it was the operator. Well, it would at least make for >a lot of conversation. There wouldn't be a dime's worth of difference. >Kinda' like the difference between Republicans and Democrats who spend a >lot of agitation over whose ox is being gored; they both equally want >your money and power. > >Jim Coleman, sr. The fact is that the particular VTD being used may make a substantial difference in the quality of the tuning of a given piano. It would be interesting to see if that difference would be substantial _enough_ to make a difference in the outcome of a tune-off. VTD's vary greatly in their tuning calculator functions; when one speaks of comparing the tuning capabilities of SAT and RCT, for example, one is, for the most part, speaking of the differences between the SAT's FAC and RCT's Chameleon 2. RCT's Chameleon, as good as it has been now for some time, is still in a constant state of development and can be incrementally improved as new discoveries are made that can improve its performance. The FAC of the SAT III is apparently mostly unchanged from the SAT II, adding only the ability to widen/narrow the 88 note tuning as a whole. (RCT's Chameleon allows any octave within the 88 note tuning to be widened/narrowed individually.) An example of a specific SAT/FAC tuning problem follows: A goodly portion of my career during the past few years has been the servicing of a single piano, a Yamaha G1R, in a jazz club. The G1R is a 5' 3" grand with plain-wire all the way down to B2. The tenor break is horrendous. How do I know this? Here are the RCT Pianalyzer numbers which document the inharmonicity of the highest wound string and the lowest plain-wire string, the two notes on either side of the break: A#2 B2 12th ptl = 20.7 cents 12th ptl = 46.6 cents 10th ptl = 15.9 cents 10th ptl = 33.0 cents 8th ptl = 10.8 cents 8th ptl = 22.4 cents 7th ptl = 8.6 cents 7th ptl = 17.4 cents 6th ptl = 7.2 cents 6th ptl = 13.5 cents 5th ptl = 6.2 cents 5th ptl = 9.9 cents 4th ptl = 6.1 cents 4th ptl = 8.4 cents 3rd ptl = 4.1 cents 3rd ptl = 5.5 cents 2nd ptl = 1.8 cents 2nd ptl = 0.2 cents 1st ptl = 0 cents 1st ptl = 0 cents Wildly high inharmonicity on B2, and relatively low inharmonicity on the A#2 right next to it! I am not picking on Yamaha; as a matter of fact, I strongly recommend Yamahas to my customers. (Two of my customers bought a C1 and a C2 respectively during this past summer on my recommendation. OK?) But there are some scaling, uh, weaknesses in the small Yamaha grands which I am familiar with because I tune so many of them. The tenor break in the current production GH1, which also has a plain-wire B2, is as bad as any piano that is commonly seen by tuners, hence my comment a few days ago that using GH1's for a tune-off would "tell the tale." I have been tuning the jazz club G1R since before RCT and this piano (with a few others that are similar) is the reason that I "outgrew" FAC. FAC tunes B2 at its 6th partial. A quick comparison of the two 6th partial readings above will suggest that there may be a problem if both of these notes are tuned from the curve drawn through the 6th partials. The high inharmonicity of B2's 6th partial would leave the 5th, 4th, 3rd, and 2nd partials too flat. Way back when, I tweaked the tuning of B2 and saved it, and I still have that tuning in my SAT. I find, looking at the tuning now, that I had to raise B2 5.5 cents away from the FAC reading, which means, as far as I am concerned, FAC made a gross tuning error on this one note. (The scaling may be gross too but that is another matter.) RCT's Chameleon 2, on the other hand, tunes B2 from the 3rd partial and, as calculated for this same G1R, the RCT-calculated reading for B2 is about the same as in my _aurally corrected_ FAC tuning. In other words, where FAC makes a gross tuning error, Ch2 makes no error at all. Tuning and taking measurements of the lowest plain-wire strings on a piano like this are very difficult. The strings exhibit remarkable instability. However, FAC's error on B2 on this piano and on current production GH1's appears to be in the area of 5-8 cents. I have been preaching the benefits of tuning the tenor plain-wire strings from the 3rd partial as RCT can do. Here is a review of those benefits: There often is aberrantly high inharmonicity in the lowest plain-wire strings, often associated with a hockey-stick shape of the tenor end of the long bridge and the resulting short speaking length of these lowest plain-wire strings. Tuning these strings from the non-octave 3rd partial in the tenor _automatically_ splits any "unanticipated" inharmonicity between the 2:1 and 4:2 octaves. In other words the octave is automatically compromised between two important sets of coincident partial pairs. Tuning the lowest plain-wire strings from the 3rd partial will mean that the 3:2 fifths formed between these strings and the notes above will be clean. (If they are tuned from the 4th or 6th partial, the third partial may be flat and the fifth formed above the note may be expanded instead of contracted.) The most common way of tuning octaves in the bass is with the 6:3 relationship. If the bass notes are tuned at the 6th partial as is common in RCT, and the plain-wire strings are tuned at the 3rd partial as they can be with RCT, then the important 6:3 relationship will be preserved by direct-interval tuning even when the inharmonicity is unexpectedly high in the lowest plain-wire strings. I am not anti-SAT by any means. But FAC makes an error in the specific situation of the B2 of some current model pianos. The error is the unfortunate result of FAC's tuning the bass notes up through B2 from the 6th partial, and some piano's plain-wire high-inharmonicity tenor extending down to B2. An SAT work-around is in order and I believe that there is one. This workaround has been suggested by my experiences with RCT. (Yes, I am suggesting that knowledge gained from RCT can help SAT tuners.) Let's assume that one tunes up from A0 chromatically to C8. As mentioned, FAC tunes the bass notes from the 6th partial. If one suspects that there may be high inharmonicity in the lowest plain-wire strings as in the B2 described above, when the tuner has tuned up through the wound strings, one could first tune B2 to its normal FAC reading, then hit the Octave Down button. The 6th partial "octave-down" reading will be at the _3rd_ partial of B2; if the display is spinning "flat" when reading B2 at the B1 reading, that means that the 6:3 octave is contracted by the amount indicated by the rate of spin. We usually expect this 6:3 octave to be stretched. One could raise the plain-wire string until the 6:3 is slightly stretched, perhaps matching the spin-rate difference between B1-B2 to the spin difference of the next door A#1-A#2. Such a procedure (that is, tuning B2 just slightly sharp of the B1 reading) might allow SAT tuners some of RCT's benefits of using the 3rd partial in the tenor. Although it might be preferable just to go ahead and buy RCT. <big grin!> Thanks for reading, Kent Swafford
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