Soft blows

[jason kanter]

see below

> -----Original Message-----
> From: pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org]On
> Behalf Of Jenneetah
> Sent: Tuesday, October 26, 2004 5:31 PM
> To: Pianotech
> Subject: Re: Soft blows
>
>
> At 9:26 AM -0700 10/26/04, jason kanter wrote:
> >... I *imagine* that you tune with
> >soft blows, then settle the pin with a hard blow, then listen again
> >with soft blow to ensure the tuning has not moved? But the hard blow
> >has likely changed the tuning, so ...
>
> Why assume this? A clean unison before the hard blow, which remains
> clean after the hard blow (and this happens more reliably as we get
> better) is contradiction of this assumption. What's more, it's a
> clearly achievable goal.

I'm not assuming it, I agree the goal is for the test blow NOT to change the
unison, but from the test blow's perpective it is intended to expose any
instability that may lurk in the unison.

...
> The "bump-up-bump-down" is what I trust.

Can you say more about this?

...
> Ten years ago I measured the side view of note C5 on a Steinway Band
> the maximum vertical displacement on that note caused a hard blow,
> and fellow NH chapter member Doug Kirkwood and I calculated the
> string friction barrier at the capo and the momentary tension spike
> of a test blow. 21 lbs vs. 3.5 ounces respectively, as I remember.

Sorry, I don't understand the experiment. Can you explain?

...
> At 11:33 AM -0700 10/26/04, jason kanter wrote:
> >Does step 2 -- the very hard staccato blow -- damage the beauty
> of the unison?
>
> Jason, can you clarify? Are you asking if a unison played softly
> immediately following the vhsb will have its beauty damage (assuming
> no change in the tuning of the unison)? Or simply whether a note
> sounds ugly when banged? (I'm assuming the latter, although Andre in
> his answer didn't seem to distinguish.)

Clarifying: I was asking the former, and I took Andre's answer to be a reply
to the former. I don't think there is any argument that hard blows
themselves produce tones that are less pleasant, have exaggerated upper
partials, etc. I was asking whether the hard blow, used purely as a means of
"proving" the stability of the unison, will damage the unison somehow, even
if the unison is afterwards played softly and is found not to have moved.
Andre seemed to say that yes, the hard staccato blow actually does damage to
the unison. I'm still scratching my head.