ETD question re: unisons

[Murray Seminuk]

Hi Roger
I'm really on a roll tonight , this is my 3rd reply.Correct me if I'm wrong
,but are you saying that you tune each string a number of times with the
RCT,then take a reading of the three together and have a pitch drop of .3
cents.I have been using a Sat for a number of year sand I find that I cannot
always use the lights to tune a unison.I do not have a RCT to do a real
comparison but I find that when the lights stop there still is a "window ''
to tune within.With my SAT a difference of .3 cents would be noticable to
the ear.I would wonder if all that has happened is that one of the strings
is not in unison.
Regards
Murray
----- Original Message -----
From: "jolly roger" <baldyam@sk.sympatico.ca>
To: <pianotech@ptg.org>
Sent: Wednesday, February 14, 2001 9:27 AM
Subject: Re: ETD question re: unisons


> Hi Howard,
>                  Yes it is easy to confirm.  The test that I have done
with
> a RCT show about a 0.3 cent drop in octave 5/6. The test was performed by
> tuning each string individually several times, to over come the
> interaction. then the net 3 string unison was measured.
> The effect is known as string coupling.
> My own theory is that. as all strings start to increase the amount of
> energy into the bridge, the board is moving through a greater excussion,
> and hence dropping the frequency a tad.
> Now I've been out to lunch before, and I could be off base on this one.
> Regards Roger
>
>
> At 10:47 AM 2/14/01 -0500, you wrote:
> >Hi everyone,
> >
> >Since I know nothing about ETD's my question might be naive. Nevertheless
> >here goes: I believe that Virgil's assertion that a 3 string unison is
> >flatter than each of the single strings heard singly, is a bit
questionable
> >or should I say not fully accepted. Wouldn't it be easy and conclusive to
> >check this thesis by using an ETD to measure this? Thanks!
> >
> >
> >Howard S. Rosen, RPT
> >7262 Angel Falls Ct.
> >Boynton Beach, Fl  33437
> >
> >hsrosen@gate.net
> >
>
>