stability of pitch raises

[Vanderhoofven]

Dear Terry,

If the piano is more than 4 cents away from the correct pitch it needs a 
separate pitch correction before the fine tuning.  If it is a concert 
tuning, the pitch needs to be within 2 cents of the correct pitch before 
doing a fine tuning.  The fine tuning follows immediately after the pitch 
raise, during the same tuning visit.  If it is a large pitch correction and 
I am running short of time, I do as many passes as I can during the normal 
tuning time and schedule a follow-up tuning as appropriate.  If I have 
enough time, I do as many passes to get a solid tuning.

If the piano is only 5 cents from the correct pitch, I might make only one 
pass, but I find that I still spend so much time checking the unisons that 
I could have gone ahead and done two passes.  A two pass tuning is more 
solid than a single pass tuning, at least for me.

If the piano is up to about 20 cents from the correct pitch It will take 2 
passes (pitch raise and fine tuning) with either RCT or SATII.  If the 
pitch is 20-50 cents from correct pitch, it will often take 2 passes with 
RCT and 3 passes with SATII for me.  If the piano is 50-100 cents from 
correct pitch, it will take 3 passes with RCT or SATII.  If the pitch is 
over 100 cents from the correct pitch it will take 3 passes with RCT and 4 
passes with SATII.  This is speaking from my personal experience.

My experience doing pitch raises is that with RCT the pitch raise seems to 
be closer to the correct pitch on every note than with SATII.  SAT does a 
nice pitch correction, but RCT is closer.

Best wishes

David Vanderhoofven
Joplin, Missouri

P.S.  And a note for Stephen Airy, I have done several pitch corrections of 
over 250 cents in 2 hours, including a fairly stable fine tuning.  It is 
possible to do the first pass with no mutes at all, but beyond the first 
pass, I find it an exercise in futility to tune without mutes.  I encourage 
you to get a tuning lever and practice tuning your own piano so you can 
have some practical experience.

And as far as building a piano as small and cheaply as possible, many piano 
makers have tried to do that and gone out of business trying to cater to 
the lowest denominator.  I personally dislike tuning small pianos and 
playing small pianos isn't that great either.  I encourage you to continue 
to study all you can about piano technology.  Perhaps you can design a 
small portable piano that weighs less than 100 lbs.  Let us know when you 
do.  I would think your greatest challenge is finding a structural material 
that is stronger than cast iron without all the weight of cast iron.

Terry Farrell wrote:

>"If the piano is more than 8 cents off pitch it should be tuned a second =
>time that day
>to even off the tension. Just think how well the piano will sound a few =
>years later..."
>
>I'm trying to understand what you are saying here Jon. Are you saying
>that if the piano is more than 8 cents flat (or sharp) you should first
>do a pitch raise, and then do a separate tuning immediately after (or
>later in the day for some reason?)? Please differentiate between tuning
>and pitch raise and how many passes you might commonly do. If a piano is
>5 cents flat do you commonly only do one pass, raising the pitch 5 cents
>while tuning? Thanks.
>
>Terry Farrell