Direct Interval Tuning

[Jim Coleman, Sr.]

Hi Dave and the rest of the list:

You wrote:

" I'd sure like to see the computer that can make
judgments whereby moving one note a little sharp or flat improves some
intervals while compromising others.  No such computer or computations
from one does or ever will replace the human ear."

Welcome to the real world. It has already been done by Steve Fairchild in
his Aural Tuning Emulator. He sells his program for $500.00. You have 
options of inputting your own personal preferences as far as Stretch is
concerned. It considers each note as to how it fits with neighboring 3rds,
10ths, octaves, double octaves, octave 5ths etc. and then makes a 
determination as to how closely it can accommodate each of those to the best
possibility. It takes several iterations of the program to finally 
determine the best location.  Isn't that what we try to do aurally 
except we try to do it in one or two passes?

As I understand it, you were driven to the measured interval method because
the SOT was not accurate enough in its note to note relationships and also
the calibration was subject to gradual change due to the nature of 
resistors. I have done a good bit of that also for the same reasons. 
When the SAT came out, those reasons disappeared. I have demonstrated over
and over that if one tunes very accurately with the SAT, you are really hard
put to make any improvements in the temperament area aurally. Learning to
utilize the 4 LED measuring with the SAT can greatly increase one's 
accuracy with the machine. I can explain that in much greater detail if
there are enough people interested in it.

One of the distinct advantages in using the SAT is that the entire 
temperament area is tuned listening to the 4th partials. In tuning 4ths, 
the 4th partial of the lower note is utilized. In tuning M3rds, the 4th 
partial of the upper note is utilized. In tuning double octaves, the 4th
partial of the lower note is utilized. In tuning single octaves, the 4th
partial of the lower note is utilized. Begins to sound like a repeating
record doesn't it. When one considers how many intervals are controlled
by the 4th partial, that makes it a very wise decision to use 4th partials.
It is well known that the first 3 partials are much more erratic (uneven in
a graph of their individual note inharmonicity curves), therefore, one
introduces more possible mismatches when using the 2nd and 3rd partials.
(I don't see how there can be any doubters among those who have an RCT
if they utilize their PianaLyzer). Also for this same reason, when one 
tunes
with a SAT the M3rds come out very smoothly graduated. The 4ths come out
a little less smooth, but still very good. The 5ths will show more 
variation. So, which would you rather have? You can't have it all. The 
physics of the scale will not allow it unless you are tuning a piano which
was designed with smooth inharmonicity principally in mind. The Walter 
piano and the original C-42 Conn (Later Janssen) pianos were the first two
designed this way. (I had a little something to do with that). Other more
recent piano designs have given at least a little more attention to that
factor in scale design. There are other things which are equally important,
so inharmonicity is not the only thing.

Excuse me, I ramble and sometimes mumble. The point is that very good 
compromises are being made daily using ETDs alone. Judgments are still left
up to the individual as to the amount of stretch that is preferred. Oh, 
and I must add that the tuning lever skill of the technician is paramount.
 We still
have many technicians who prefer equal 3rds and 10ths. That's OK. They just
have to stretch more in the 5th octave if they desire any pretense of good
balance in matching single double and triple octaves. I prefer to start with
a little more stretch in the center, it makes it a little easier to 
accomplish the overall balance.

If anyone has doubts about the ability to tune accurately with just the ETD
(SAT is my preference), just attend my 3 hour advanced tuning class in
Providence where I will demonstrate the basis for good aural tuning as well
as the basis for good Electronic tuning. You will also get a chance to see
and hear the Pure 5ths Temperament as it is spread over the entire piano.
Sure, it will stretch your credulity in the midrange, but when you hear 
music played on it, I predict you will love it as many who have gone before
you have done. I am not even saying that that is the way to always tune, but
it is one way and is quite satisfying.

Jim Coleman, Sr.