tuning two pianos together

[John Formsma]

Today was a first for me...tuning two pianos for a duo-piano "concert."

Piano 1 is a Steinway D. Piano 2 is a Weber WG-60 (or something like
that model # - the piano is about six feet long).

Pretty easy to hear why it's recommended to have similar sized/scaled
pianos to use together. :)

How do you machine tuners tune two dissimilar pianos together? Tune
each to the ideal settings of the machine and call it good? Do you
play octaves and/or chromatically on both pianos together to see how
well they match? How do you make changes, or do you?

Today was not an ideal situation in other ways. The Weber was 5-9
cents flat. Also, either the A/C wasn't working, or someone forgot to
turn it down because it was 80F on stage. I shudder to think about
what will happen when the A/C brings the temp down. I'll be back
tomorrow night to retune, but don't look forward to another pitch
correction on the D.

Here's what I did, and you guys tell me what you would have done differently.

Pitch raise the Weber, then tune with open unisons to get the most
expanded tuning as will fit the piano. Tune the D with felt strips to
get a more contracted tuning. I started out tuning the A4-A3 octave to
match the Weber as best as possible. At various points up and down the
scale, I would play the same notes on each piano together to see if I
was getting off anywhere. Chromatically, fairly quickly. Then, adjust
octave stretch to better match the Weber without making the D sound
noticeably out of tune with itself. Generally, the D was slightly
contracted compared to what I would have done for solo use. In the
bass of the Weber, I had tuned the octaves a bit wide, hoping that
they would match with the D. It worked out pretty well, although you
wouldn't call it perfectly in tune. But it was pretty close, and seems
to be the right thing to have done.

What was strangely cool was figuring out whether the D was flat or
sharp to the corresponding notes of the Weber. I mean, you're
listening to the same note on each piano, and one is "off." Is it
sharp or flat? Well, you can't play the note on the Weber and tune the
one on the D unless you have three hands. So I got that figured out
after a minute of thinking. It's merely doing our "regular" interval
tests on the notes of different pianos...one with the left hand and
one with the right - well, that's kinda fun. In a demented sort of way
as it seemed to screw up the brain in all kinds of weird directions.
But it certainly keeps one on his toes.

Any input appreciated.

JF