pitch raising the bass

[Fred Yonley]

You  hear about pitch raising in regard to the midrange on up, but one does
not hear much about pitch raising the bass.   If the mid on up is about 30
cents low, I tune to 10 cents sharp on the first pass.  I think this is
standard for most tuners.  For the bass I have found that if the bass were
about 30 cents low that the amount to tune sharp would be 30 cents divided
by 3 = 10 cents divided by 2 = 5 cents.  In other words the bass drops
about 1/2 as much as the rest of the piano.  I do not strip off the bass.
I tune the unisons as I go down.  The first 3 or 4 notes just above the
break act more like the bass whether they are wound strings or plain wire;
in other words the 1/3 sharp is too much. When I was a strictly aural
tuner, pitch raising the bass was somewhat of a guess.  With an electronic
device it is much less that way.

Does anyone else use this method or have I discovered something?  Does the
bass drop less because the bass bridge is closer to the edge of the
soundboard?  I am not totally clear on all the mechanics involved.

Fred Yonley RPT