Treble unison tuning (was-Let me introduce myself)

[Warren Fisher]

Pat,

I also had a lot of trouble getting treble strings to stay put when I first
started.  I solved the problem by analyzing what I was doing with the tuning
lever and the audible pitch of the string while I setting the pin in  place.

Let me make several general statements before we get started.
1. The audible pitch you hear while tuning is coming from the speaking length of
the string.  (pretty basic, but keep it in mind)
2. The amount of audible pitch change for a given amount of pin movement
increases as you go from bass to treble.  This is obvious if you are using a SAT.

3.  Audible pitch change that you hear before the pin moves can give a false
impression of where the pin is.  A tight pin does more of this than a loose one.
What this means is with a tight pin you can pull it up and then go back to
correct pitch and set it with a good blow and if the pin hasn't been turned
enough, it will go flat within the next 5 to 10 minutes.  It also works the other
way.  Too much turn and it will go back sharp after you set it. High bearing
point friction can also cause this.  The pin moves but the audible pitch doesn't.

4.  High friction on the string bearing surfaces (understring felt, capo, V-bar,
agraffe, & bridge)  further delay the change of the audible pitch. See the
archives about lubricants that can be used on these surfaces.
5. New tuners can't feel these differences.  They just notice that the bass is
easy to tune, the middle is so-so and the treble is a son-of-a-gun!  Seasoned
tuners make allowances for these differences automatically.

Now, keeping these factors in mind, let's see if we can point you in the right
direction.

First, tune several notes in the middle.  Paying close attention to the tightness
of the pins and whether there is a delay between pin movement and audible pitch
change.  Try to sense what the average pin feels like as you tune it.  Put it on
correct pitch, give it one medium test blow and go on to the next pin. Try to do
each pin with the same amount of movement and test blow. Don't worry if it is not
perfectly tuned, this is just a training exercise. Be as consistent as you can.

Next go up to somewhere in the sixth octave (C6-B6) and tune the same amount of
notes in the same manner.  You should be able to notice that it takes more
audible pitch change to feel the pin  move than it does in the middle. Keep
turning the pin in the small increments until the string pitch stays close the
correct pitch with a medium test blow.  Don't be afraid to go back below the
correct pitch and take another run at it if you think you've gone too sharp.  If
you are approaching correct pitch from the sharp side, and suddenly the pin moves
toward the flat side and stops on the correct pitch, you should suspect that it
will continue going flat in most cases.  Go up slightly and set it again. Be
careful not to go way sharp or a broken string will result.

What this means is that generally it takes slightly more audible pitch change
sharp in the treble in order to get the tuning pin and all the various segments
of the string in balance with each other so that the string pitch doesn't wander
flat afterwards.

When you pull the pin to the sharp side then head flat towards the correct pitch,
your initial lever movement will change the audible pitch rapidly as the lever
removes the residual torsion from the pin caused by the pull.  Then the rate
change will get slower and slower until you feel the pin move toward the flat
position and audible pitch begins changing rapidly again.  If you can arrive on
correct pitch with a slight amount of torsion toward the sharp side then the
string pitch will be less likely to change.

When you have pulled in all three strings on a treble unison,  the first thing
you should check is the string pitch of the first string you tuned.  If the
audible pitch has gone flat, the pin is in the wrong position, you need to
correct it first before you finish tuning the unison or you will be chasing it as
it goes flat.  Another factor comes into play when you try to tune up a string
where you should have raised the pitch first.  Just pulling in the other two
strings will make the whole unison go slightly flat and as you tune further up
the piano, they will go still flatter.


Be consistent in your movements, allowing for friction effects, raise the pitch
on any sections of the piano that are unusally flat compared to the piano as a
whole and you will soon have the hang of it.

Good luck!



Mckenziepk@cs.com wrote:

Here is my first question, what is your advice in getting unisons in the last

> two treble octaves to stay put.  I've gotten to where I can hear  them
> alright if I turn my head the right way, but am having trouble getting them
> to stay put.  No problems in the rest of the piano. Should I use less
> forcefull tuning blows?  I bang it pretty hard. Thoughts, opinions?
>
> Best regards,
>
> Pat McKenzie

--
Warren Fisher RPT
fish@Communique.net
1422 Briarwood Dr.
Slidell, LA 70458-3102