Laptop Computer Tuner

[Yardbird47@aol.com]

Randy Potter rote, 12/30:
<<Your friend in Provo may be a day late and a dollar short. Dean Reyburn has
been working on such a program for over a year, and last summer, at the PTG
Convention in Albuquerque, I went up to his room and test drove it. It was
not *ready* yet, at least he was not selling it yet, but it worked - and it
worked good! I am going to get one>>

If I understand the original post, what the ex-Novell engineer had in mind
was linking a spreadsheet to a sound card. The laptop's mike would assay the
inharmonicity of sample notes from the piano (Dr. Sanderson's F-A-C, or just
as easily all 88, as Steve Fairchild has done). These values would be plugged
into a spreadsheet which would cipher the temperament octave frequencies
which would most evenly distribute the disharmony (read beat rates) for all
of the significant interval series residing in that temperament octave. (The
math is well beyond my high school education, but involves regressions and
interations. Both Sanderson and Fairchild have done this. My guess is that
among engineers, the math is a common garden variety.) Once the temperament
octave has been calculated, its translation to the outer reaches of the
compass involves far fewer lumps to be smoothed out.

The spreadsheet having done its job, the computer (with the DSP on its sound
card) compares the fundamental frequency of a given note from the piano to
its frequency as specified by the spreadsheet. Presumably, if the pitch of
the piano's note was within a quarter tone, you wouldn't even need to tell
the computer which note was played on the piano. When the two frequencies
match, a little thumbs-up icon would appear, and you'd move on to the next.
How about the inevitable warp and drift in the shadows behind you? Again, if
the dsp was worth anything, you should be able to run a fast chroamtic scale
over the regions already done, and the computer could to detect (even at 8-10
notes sampled each second) frequencies which were logged as tuned, but not
matching the spreadsheet specifications.

It sounds like an interesting challenge for a start-up engineer. But if he
has done his market research, he will have turned up two facts. First, it is
the experience of those human beings most likely to get a good tuning out of
a piano (namely, we professionals) that an electronic device will be a help
in producing a good tuning, only in the hands of an experienced human being.
DIYers and otherwise hobbyists who can actually hear the difference between a
good and bad tuning will find that whatever has been built into the program
is not the stuff required to make the difference between a good and a bad
tuning. Those entry level duffers who can't hear the difference will quickly
have only themselves listening to their tunings. The market forecast
according to this? The majority of purchasers without professional piano
technicians' experience will be excersizing their 30-day money back option.
The second fact is that the purchasers with technical experience will be
those who now envy Dr. Sanderson's ability to create harmonious tunings on a
three note sample, and would like that capability out in the field, at the
piano, on their lap and with a few keystrokes. If so, the accuracy of the
sound card's hearing is going to need to match if not best that of the SAT
II. If the development and manufacturing costs of the SAT II hardware, as
paid for by the small size of Inventronic's market (whatever size that may
be), set the cost of that whole box of hardware at around $1500 (a dedicated
machine for a niche market), I wish this engineer luck in accomplishing the
same with an off-the-shelf soundcard.
If he can do this succefully, I'm sure that his spreadsheet pages can be
accessed and cataloged nicely by the personal information manager tailored
for piano service, which Dean showed Randy.

BTW, this technology is well-developed by now. The *RoboTunerr* was one of
first Inventronic/Mitsubishi joint ventures, and has been covered on an
annual basis by the WoolEyes New Service.

Bill Ballard RPT
NH Chapt.

"You'll make more money selling my advice than following it" Steve Forbes,
quoting his father, Malcom.