piano/violin

[Farrell]

I think the word resonate, as applied to the piano string/soundboard
interaction, lacks an adequately precise definition for our use.

Consider the following definitions from Webster's:

Resonance:
A) "Reinforcement and prolongation of a sound by reflection or by vibration
of other bodies."
B) " in physics, the reinforced vibration of a body exposed to the vibration
at about the same frequency, of another body."

Resonant: "Increasing the intensity of sounds by sympathetic vibration; as,
resonant walls."

It seems to me there are two distinct ways to view the property of resonance
with respect to the piano string/soundboard interaction: 1) the soundboard
can be said to resonate directly by the string vibration (via physical
movement of the bridge), and that in turn makes the board resonate (or
vibrate - same thing here) (definition A for "resonance" would work here);
or 2) an area of the soundboard resonating via sympathetic vibration from
the sound originating in another area of the soundboard (via transfer of
energy by soundwaves through air).

I have thought that resonance is restricted to a situation where an object
is set into vibrational motion via AIR movement. So, in this case, #1 is
false in that we are not talking about the board resonating, but rather
vibrating via transfer of energy from the string to the board via the
bridge. #2 would be true - given my definition, this is resonance -
something presumably undesirable in a piano soundboard.

Consider David's statement:

> Of course it should resonate! (vibrate sympathetically with the source
> of sound, i.e. the vibrating string.  How else does it transfer its
> vibrations to the air?  The word resonate (precise definitions of
electrical
> & physical resonance notwithstanding)  means 'to resound, to vibrate
> sympathetically with some source of sound', which string instrument tops

I think he is using the term resonate to describe the transfer of
vibrational energy from the string to the soundboard via the bridge
(inconsistent with my understanding of proper use of the term "resonate").
He uses the term "sympathetically". Is this meant to say that the board
resonates at the same frequency as the string (via the bridge), or is it
meant to say that the string vibrates, moves air, and the board is set into
motion via the moving air? He MAY simply be saying here that the soundboard
resonates with the strings (via the bridge). In this case, my understanding
of proper/accepted use of the term is inconsistent with David's - the board
is not resonating with the strings, but rather it is vibrating as a direct
transfer of energy from the strings to the board via the bridge.

My understanding of Del's statement:

> Second, piano soundboards should not resonate.
> They do, of course, but it would be best if they did
> not. And, while I don't
> know anything about violin design I rather suspect
> that violin soundboards
> shouldn't resonate either.

(and please correct me if I am off base Del) - is that the soundboard
vibrating as a direct transfer of energy from the strings to the board via
the bridge is not resonance (perhaps we should use a term such as "primary
soundboard vibration" for this?). He uses the term "resonate/resonance" to
mean sympathetic vibration of an area of the soundboard due to vibration of
another area of the soundboard (i.e., a primary vibration of the soundboard
occurs via transfer of energy from the strings, which causes the transfer of
sound through the air, which in turn causes a sympathetic vibration of
another area of the soundboard - and hence, the undesirable occurrence of a
soundboard resonating).

Sorry if this was just too much verbiage to draw a distinction between two
definitions of a term. I just thought it important to clearly understand
that there is a difference (I sure hope I am like not totally wrong on all
this).

I know that some angles of this thread have gone on too far to do anyone any
good, but I, for one, have sure picked up quite a bit of information to
process from it. Thanks Del and all others that have provided input.

Terry Farrell

----- Original Message -----
From: "Dave Nereson" <dnereson@dimensional.com>
To: <pianotech@ptg.org>
Sent: Sunday, June 10, 2001 5:36 AM
Subject: piano/violin


> --- Delwin D Fandrich <pianobuilders@olynet.com>
> wrote:
> >There are no similarities at all in how
> > their tone producing
> > mechanisms work.       (violins and pianos)
>
> I disagree with this.  A violin has strings under tension, deflected
upwards
> by a bridge resting on a large, convex sheet of wood that's designed to
act
> as a diaphragm or drum head, in a way, that is,  to vibrate.   However,  I
> agree that there the similarities end, since the violin top is carved from
> hardwood whereas the piano soundboard is "boards" butted together side by
> side, glued, then arched, or made convex.  Then there's the obvious
> difference of violin strings being plucked or bowed whereas the piano's
are
> struck.
>
> > Second, piano soundboards should not resonate.
> > They do, of course, but it would be best if they did
> > not. And, while I don't
> > know anything about violin design I rather suspect
> > that violin soundboards
> > shouldn't resonate either.
>
>      Of course it should resonate! (vibrate sympathetically with the
source
> of sound, i.e. the vibrating string.  How else does it transfer its
> vibrations to the air?  The word resonate (precise definitions of
electrical
> & physical resonance notwithstanding)  means 'to resound, to vibrate
> sympathetically with some source of sound', which string instrument tops &
> backs,
> bottom drumheads,  piano soundboards, and duplex scales do, and also
window
> panes when jets or loud trucks go by.   Another difference between fiddles
>  and pianners is that the violin also
> has a back and the whole assembly creates an oddly-shaped "box", or
> resonating chamber, with the top and bottom connected by a soundpost.  The
> box is a place for the sound to resonate.  If you took the back off, it
> would sound quite different indeed.  I didn't say the whole body of the
> violin is always "in resonance" with whatever note is being played, but
the
> soundwaves in the air inside the violin might be.   Vertical pianos, with
> their lower cavity behind the bottom panel, have something of a
"resonating
> chamber", it seems to me -- if you yell or drop a heavy tool into them,
they
> echo, like a cave.  Grands don't do this as much, unless the lid is
closed.
> What this all means, I don't know -- my main point is that the string
> instruments and pianos do have SOME similarities, and that resonance,
> or resonating, depending on your definitions,  is
> definitely involved.   --Dave Nereson, RPT, cellist, pianist, nit-picker
>
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