stability of pitch raises

[jolly roger]

Hi Tom,
              The RCT is remembering where it has been, and is constantly
recalculating the over pull for the pitch raise as it works it's way up the
scale.   The pitch raise is done very quickly compared to setting a
temperament and working out from the centre, using traditional aural
techniques.
Another advantage is that the note you are tuning is not being referenced
to a moving target.  If with experience you select the correct over pull,
the piano will be with a few cents of where you want to be.   So close that
your fine tuning is not significantly altering the tension within the piano.
I am willing to bet that there is not 1% of tuners out there that could run
Neck to neck with the high end ETD's,  for speed and stability, giving a
good tuner that knows how to use his ETD.

A new use I found for my RCT last year,  This time of the year University
and Institution Yamaha U1's are typically. 5-10 cents sharp overall but the
first dozen notes on the tenor bridge is up to 35 cents sharp.  Summer
humidity plays havoc in this area.

If the pianos were left alone to mid Nov it will come back close to pitch,
once the heating kicks in. It was a pain doing these two major pitch
corrections.

Now I set tune to A441.  Set for pitch correction mode,  and tune the first
dozen notes of the tenor bridge.
Then do a single pass tuning.
The tuning is more than passable for the practice rooms.

Once the piano dries down, later in the year,   An A440 tuning is much
easier, and the overall stability is much better with both tunings.

OK  So I am prone to cheating at times.  With hardly any budget I have to
make choices.  I have never heard one comment that the piano has been tuned
at A441.   But Wow! they sure scream about the octaves at the end of the
tenor bridge, at this time of year.

This model of piano is so wild at the end of the bridge, this process cause
less over all trauma, to my way of thinking.

Regards Roger




At 09:56 PM 8/29/01 -0400, you wrote:
>I do all my pitch raises using RCT, so I end up very close to pitch after
the 
>first pass.  If the piano is 50 cents flat or more, I have always warned the 
>client that a pitch-raised tuning is a less stable tuning, and that their 
>piano may need another tuning in 3 or 4 months.   Rarely do they actually 
>call me in 3 months.  Most often I come back in a year...OR TWO, and I am 
>usually surprised at how well the piano has stayed in tune.  Not that the 
>piano doesn't need a tuning, but it's tolerable enough that I can understand 
>why I haven't been called back sooner.  I suppose it's possible that the 
>piano did all its drifting in the first 3 months, and just stayed there, but 
>I'm starting to wonder about the conventional wisdom that a pitch-raised 
>tuning is less stable.  
>
>Could it be that the use of the RCT negates the instability issue by virtue 
>of getting the piano so close to pitch after the first pass?
>
>Any thoughts?
>
>Tom Sivak
>