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RE: Reproducer's "Voice"
By Craig Brougher

I have rebuilt a lot of reproducers  and heard many in other homes,
and never heard one that I thought was too loud.  Now that's dedication!
But frankly, there's more to that statement than it sounds like at
first glance.

   From huge concert grands to small spinet-types, reproducers come in
all makes and sizes, but are acoustic instruments, and develop their
"power" as much from the room and the height of ceiling they are in as
from any other factor.  A concert grand in a small room is not
painfully loud, I think because of the hemholtz principle.  loudness is
a measure of both energy flux and pitch.  The energy of a hammer
imparted to a string is directly proportional to the energy you are
going to get out of that string, given the same pitch.  So what is
hurting our ears in some cases is something other than just loudness.

   I cannot be denied that some pianos are far more powerful than
others.  One instrument, a concert Chickering built around 1850, had a
top end of about 126 db.  In a recording studio, that piano caused the
pianist's ears to ring for two days afterward.  It was so powerful it
could compete with a symphony orchestra.

   They don't make pianos that powerful today, for that very reason.  So
I suspect that what is being interpreted as "too loud" has its roots
elsewhere.  The Duo-Art test roll is not the end-all and be-all of the
regulation of a Duo-Art.  In the case of a Duo-Art, it is where the
regulator _begins_ his regulation.  The real regulation starts by
playing of twenty or thirty rolls and touching up to each one, and then
going back and forth between certain passages that need adjustment, and
finally compromising them all in such a way that even the most
difficult D/A rolls are able to play effortlessly.  Sorry, but the D/A
is an exercise in the fine art of compromise, if you want it really
good.  The reason is, it is not self-compensating.  It relies totally
upon the roll coding to think for it, to position its spill valve, and
to provide enough power in certain passages depending on the number of
notes being played down at one time.  The other reproducers are not like
this.  Thus, compromise is necessary between special rolls that the
rebuilder knows are "marginally coded," as well as ordinary rolls.

   Terry Smythe had a very good idea regarding the voicing.  Softening
the hammers, closing the lid of the piano, and even sometimes adjusting
your hearing aid (if that applies) may be necessary.  The problems with
the closing of the lid is, it greatly compresses the expression one is
able to realize by damping out the power of the string partials, which
to the ear tells it "loud, louder, loudest."  Because of the acoustic
nature of strings, they rely on the room's own "impedance" to cause
them to fully develop.  So when the lid is down the impedance is maximum
and actually helps to dampen out the strings, in addition to closing
the "door" to the room the piano is in.  It changes the tone quality,
the resonance of the partials, the ratios of the partials, everything.

   I have always wondered, "why go to the expense of buying a top
quality grand piano and then use it as a table?" If Authur Rubenstein
sat down to play their own piano, would they tell him, "Just a minute,
please," and then close the lid? Oh well, everybody has their own way.

Craig B.



(Message sent Wed, 8 May 96 15:53:45 UT , from time zone +0000.)

Key Words in Subject:  Reproducer's, Voice