Upright and Grand rims, was: Impressive Steinway Upright

Tony Caught caute@optusnet.com.au
Sun, 15 Sep 2002 22:44:59 +0930


Hi Terry,


> A few comments and questions interspersed below:
>
> Terry Farrell
>
> ----- Original Message -----
> From: "Tony Caught" <caute@optusnet.com.au>
> To: "Pianotech" <pianotech@ptg.org>
> Sent: Sunday, September 15, 2002 12:19 AM
> Subject: Re: Impressive Steinway Upright
>
>
> > Alan, Terry,
> >
> > A soundboard should be totally under the influence of the strings. By
saying
> > that I mean that any part of the soundboard that is not immediately and
> > directly influenced by the strings should be made dead.
> > This is done by putting cut-off bars across (usually the corner
sections)
> > the soundboard to stop that section from vibrating with the strings.
>
> So, doesn't that mean that soundboard area is under the influence of the
strings?

Yes, when cutoff bars are fitted.
>
> > As an example,
> > When the piano is played with the dampers off the strings, all the
strings
> > are vibrating as is the soundboard. When the dampers re-engage the
strings
> > the strings (hopefully) stop vibrating and so should the soundboard.
> > In a board with no cut-off or dumb bar, some sections, i.e. the corner
> > sections, carry on vibrating with rubbish sounds that linger on.
>
> Really? Is this a way to increase sustain? "Rubbish sounds": is that kinda
like many duplex scales?

No, it does not increase sustain, sustain is how long the strings ring. I am
talking about when the dampers reengage the strings to stop them vibrating,
the soundboard should also stop vibrating. Which it does.
Except for those areas not under direct control of the strings. These areas
still vibrate at random frequencies for a short time.
Rubish sounds are kinda like a composite of all the strings ringing at one
time, in reduced form of course, Duplex scales / sounds are generally of the
higher frequencies, these left over sounds are generally of lower
frequencies. Think of a wopple board sound.
>
> > When played without using the damper pedal, these areas keep sounding
the
> > vibrations of previous notes played thus muddling the sound that the
> > listener hears.
> > One of the major differences between uprights and grands is related to
this
> > factor.
>
> I don't understand. How do uprights and grands differ in this respect?

Please reread "When you look at a grand soundboard you can see ......

>
> > When you listen to a grand the sound is cleaner that in most uprights
> > because of this.
>
> Like a Yamaha? Some folks criticise this type of sound.

No.  I think the Yamaha clean sound that you may be refering to is the one
caused by thicker soundboards, greater tension on the strings and harder
hammers.
The clean sound that I am refering to is, when a note is played and stopped
there is no sound. When a series of notes are played and stopped, the notes
do not run in together. Dampers may be perfect but still in some pianos you
get the effect that the dampers are not working as they should. They are,
but some areas of the soundboard are still producing audible sound.
>
> >  When you look at a grand soundboard you can see that the
> > rim of the piano virtually follows the shape of the bridge and the
cut-off
> > bar cuts off the uncontrollable section of the soundboard in the bass
corner
> > of the board. The cut-off bar can also be in line with the treble bridge
to
> > also keep more balance to the board.
>
> Makes sense.
>
> > Were a soundboard "rimmed the same as a grand piano" that is in relation
to
> > the bridges, then the upright would give the same output of sound as the
> > grand.
>
> Specifically, what do you mean here? How does a grand rim necessarily
differ from an upright rim? Are you speaking of the most common modern grand
rim that is laminated vs. the most common upright rim that is solid
timbers - or at least straight pieces of wood? Why would that make a
difference? I have an Everett grand in my shop with a solid-timber rim - and
the S&S upright with the laminated rim. But what would make one necessarily
sound better/different than the other.
>
I am referring not to the rims construction but to the location of the edge
of the soundboard in relation to the bridges. Naturally the rim is important
to be solid but that is another tonal issue relating to the soundboard but
not this one.
Cost is the deciding factor in upright pianos. It is easier to not have any
cutoff bars (cheap pianos) Next a straight cutoff bar at the top left hand
side corner (medium price pianos) Next a shaped cutoff bar at the top left
hand side corner with a shaped cutoff bar between the treble and bass
bridges. (expensive pianos, mainly old expensive pianos. Next ask Del, he
may let go with some super secret shape that he has in his mind that hasn't
been fully developed yet.

Actually the S&S upright that you have with the laminated rim may be the
last one I described.


Regards

Tony Caught
caute@optusnet.com.au



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