tuning sequence

[McNeilTom@aol.com]

Dick Beaton, & List:

I'm embarrassed to admit that it took me a couple of decades of practical
tuning experience to 'discover'  a factor influencing the sequence of tuning
the strings of a unison in vertical pianos.

It seems that the tuning pin arrays of most uprights are designed (or at
least built) so that the some of the pins interfere with neighboring strings.
 This condition is usually worst in the tenor area, worst in pianos where the
tenor strings are at a considerable angle from vertical, worst in short
pianos, i.e., spinets, and of course worst in pianos carelessly made.  The
interference is most objectionable when the left string of a unison (upper
row of tuning pins) bears against the lowest tuning pin of the note to its
left.  If one tunes the lower pin (right string) of one note, then moves
toward the treble, tuning the left string of the next note, there is no
appreciable problem.  The change in string tension in tuning the second
string is slight and has little influence on the pin already set.  However,
if one tunes the left string of the upper note first, then the right string
of the lower neighbor, there may be trouble.  The 'flagpoling' of the lower
tuning pin may upset the tension of the string already tuned.

So, if you strip-mute in the tenor area of verticals, you will often have
better unisons if you pull out your strip from left to right, tuning the
upper pin first, then the lower before moving on to the next note.

Grands are seldom problematic in this way, and the same goes for treble and
bass regions of most uprights.  But it doesn't hurt to be aware of this
potential problem and apply a sequence that won't undo your best unison
tuning.

  -     Tom McNeil, RPT     -
Vermont Piano Restorations