FAC Averaging

[Billbrpt@AOL.COM]

In a message dated 11/17/98 3:17:06 PM Central Standard Time, atodd@UH.EDU
writes:

<< List,
 
   I'd like to know if anyone using a SAT has ever tried averaging the FAC
 readings when tuning two pianos together. I'm referring primarily to
 teaching studios/practice rooms with two pianos in them.
    Each one would not be tuned to it's best possible tuning, but would they
 sound better together and OK separately?
    My normal practice is to tune the "lead" piano its best and tune the
 second piano to it. That's what I do in concert situations. Each piano has
 its best tuning stored on a page of memory and whichever is the second
 piano gets the same tuning as the lead piano.
    What brought this up is yesterday I tuned a Steinway B and a Steinway S
 in a private piano teacher's home. The pianos are a little better matched
 in size in our two-piano rooms here at school, so it got me to thinking.
    This time, I went ahead and tuned the 'S' to the same tuning I used for
 the 'B' and it sounded fairly good. And in this situation, it'll probably be
 OK.
    For your information, the FAC readings were:
 
   'B'                        'S'
 F = 7.1                    F = 8.9
 A = 8.3                    A = 9.2
 C = 6.3                    C = 7.2
 
    Just wondering. Thanks.
 
 Avery
  >>

Although I, personally do not use the SAT this way, I can tell you that people
have done both of what you have said and had what they considered good
results.

I think there can be even a third alternative that you will find just as
acceptable if not even better:  tune each one to its own program, just make
sure that your starting pitch is exactly the same for both.

You have probably gathered by the many discussions here that there can be a
variety of acceptable ways to tune any piano.  By varying the pitch, the
temperament and the stretch in the octaves, you really can have a virtually
infinite number of possibilities.  It is your goal and decision to do what you
think is best depending on the circumstances and the expressed wishes of the
customer or artist.

You have to bear in mind that two instruments, be they two pianos or any other
two, do not necessarily need to be tuned *exactly* the same in order for them
to be *perceived* as being in tune with each other.  So even though you may
wish to be very precise in accomplishing whatever decision you have made with
any given piano, this does not mean that different choices made with another
piano will make the two incompatible.

Furthermore, you have to assume that the two instruments will not be playing
the same exact notes at the same time.  Otherwise, why would there be two?
Presumably, one is a solo instrument, one is an accompaniment.  Perhaps it is
music for two pianos, four hands.  One will be mostly one register and one in
another.  Therefore any requirement of exact unisons between the two is a moot
point.  The two pianos will each have a different character anyway.  They are
also playing different parts.

  The difference in the two FAC programs is the way in which theoretical ET
has been "stretched" out to accommodate inharmonicity. Even if you tune each
very carefully to its own program (but each starting on exactly the same
pitch) and you play the same unisons on each piano, you are not likely to get
enough difference between the two to be considered *musically* out of tune.

This is the logic that I use when I am asked to "tune the piano *to* the
organ" in a church.  I simply measure and record the A4 of the organ and use
that as the pitch for the piano.  Most electronic organs are at standard
pitch.  Even in the case of a pipe organ that is not at standard pitch and
whose temperament may be further from theoretical ET than my own (either by
design or default), I still use the same approach, have tested it many times
and was satisfied and have never had a complaint about it.

I suggest using the same approach when tuning a group of pianos such as at a
school.  Choose an individual program for each, whatever it may be, but tune
each to the same exact starting pitch.  They will all be perfectly compatible
and each the best they can be.

Sincerely,

Bill Bremmer RPT
Madison, Wisconsin