pitch raising

[Newton Hunt]

> "NO" to that notion, and says one should tell the customer
>  "It will take three tunings, two weeks apart",Hi Les,

I have always considered the an excuse to get extra money
from a customer without mechanical or aesthetic
justification.

through a piano will not stay "perfectly" after a two or
three tuning at one visit but the difference between the two
is negligible at worst and non exist ant at best unless
there is a mechanical problem (back separation, cracked
plate type of thing) that would manifest itself during the
first and second tuning.

hat occurs during a pitch raise is stress is being exerted
primarily on the plate struts and comparatively little on
the soundboard and the wooden structure except as the plate
needs to accommodate the compression on the struts and pulls
the case along with it.

To prove this the next time you are going to unstring a
piano carefully measure the pitch of each note, remove the
bass strings then remeasure each note.  Plot the
_differences_ and the graph will show that change from
tension removal does not cross the middle / tenor break
strut to any appreciable amount.  Logic then dictates the
compression is on the plate struts and not so much anywhere
else.

So one tuning to get the piano up to pitch and a second
tuning to do a fine tuning.  If the pitch raise is done
properly then the piano will be in tunable condition for
customer use immediately.

There is essentially no difference between a "poor" and a
"superior" piano in terms of pitch return.  If you are using
an ETD and tuning each note and unison as you go along then
an increase of 25% will work well.  If you do this aurally
then the compensation is about 30%.  What is good about an
ETD is adjustments to variations of pitch change from
section to section and in various locations in any one
section.  Such corrections are more difficult doing an aural
tuning.

There are exceptions to the above generalities and they are
the ones that will come and a bite you in the backside and
you will have no choice but to tune and piano a third time. 
Lester spinets, Whitneys, Baldwin grands and old Mason &
Hamlins come to mind as opposites on the stability scale.

Tightening the plate bolts and screws can be helpful for
stability as well.

		Newton