EBVT..for Tom Seay

Phil Bondi tito@PhilBondi.com
Sat, 28 Oct 2000 07:51:19 -0400


HT enthusiasts:

Based on aural tuning directions that Bill Bremmer provided, I
have calculated the following offsets for his EBVT temperament:

F      3.10
F#    -1.28
G      4.50
G#     2.49
A      0.00
A#     1.63
B      0.58
C      5.35
C#     0.98
D      1.81
D#     2.00
E     -0.86

or, if you prefer offsets that are more zero-centered:

F      1.41
F#    -2.97
G      2.81
G#     0.80
A     -1.69
A#    -0.06
B     -1.11
C      3.66
C#    -0.71
D      0.12
D#     0.31
E     -2.55

In finding these offsets I developed a software tool called
the Temperament Designer which can hopefully help to translate 
aural tuning instructions into offsets from ET for other 
"historical" temperaments as well.

One difficulty in translating aural instructions is that they
depend somewhat on inharmonicity.  So the computer program that
I designed uses an ET tuning file and an inharmonicity file on
which the calculation of beats is based.  Then it provides the
ability to modify the ET tuning according to aural instructions
based on interval beats.  Once the program was written, it took me
about 10 minutes to follow the aural instructions for Bill's EBVT
and derive a "virtual tuning".  Then the offsets for a temperament
octave are written out to a file which can be read into TuneLab,
or manually entered into an SAT or RCT.

The effect of inharmonicity in this process, while noticeable,
is small.  Therefore I have every hope that the offsets derived
based on the "typical" inharmonicity data that I used will apply
equally well to most pianos.  I also investigated the effect of
starting with two different "ET" tuning curves using different
partials.  That also did not affect the outcome very much, as long
as the ET tuning curve was a reasonably good match to the 
inharmonicity.

I have a little more clean up to do on the program before I make
it available on my website, but I wanted to get this preliminary
result out because of the interest in the EBVT numbers.

-Robert Scott
 Real-Time Specialties




This PTG archive page provided courtesy of Moy Piano Service, LLC