test blows, unisons, intervals

[David Love]

I thought that statement might get me in trouble.  I meant it really as a
self diagnostic in the short term, not necessarily reliable on a piano that
has been through the ringer, so to speak.  When you say they were calling
you back, did they expect that the piano would hold its tune after what it
went through?  I hope you are not tuning it for free.  I don't guarantee
tunings for any length of time.  There are too many factors that can cause
it to go out of tune that are beyond the tuners control.  The situation you
describe is one of those.  I have not found that strings on a particular
unison go out of tune at different rates and I don't tune the left or right
string differently than any other string.  I have not had the experience
you describe--at least not on a piano with an uncompromised pinblock.  I do
frequently find that I come to pianos that I tuned 6 months ago and the
unisons are all nice and tight, but the intervals have drifted out along
with the pitch due to changes in humidity and, presumably, different rates
of expansion in different parts of the board.   It's hard for me to comment
on the reason this may have happened. 

David Love
davidlovepianos@earthlink.net


----- Original Message ----- 
From: 
To: pianotech@ptg.org
Sent: 8/19/2003 10:43:50 PM 
Subject: Re: test blows, unisons, intervals





As a general rule, if unisons go out it's your technique, if the intervals
>go out while the unisons stay solid, it's the environment.  There are, of
>course, always mitigating factors


the other day I was called back on a piano I had tuned at the end of June.
Several unisons were way off. I know that the humidity level changed
drastically. (The owners went away for a month leaving the piano in a very
hot house, came back and turned on the evaporative cooler) What surprised
me though is that of the 8 or 9 trichords I adjusted it was always the
right string that was off, the lower pins in other words. The whole piano
was sharp of course but the intervals were pretty much ok except for one
octave in the bass.
So what do you think is it my technique? is it because the right strings
are shorter that they behave differently? Do you use a different technique
for the left and right strings? 
the piano is a Yamaha U1

Jean-Luc Matton