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From: rdp@teddy.UUCP
Newsgroups: net.audio
Subject: Re: Random stuff...
Message-ID: <1264@teddy.UUCP>
Date: Thu, 5-Sep-85 12:45:47 EDT
Article-I.D.: teddy.1264
Posted: Thu Sep  5 12:45:47 1985
Date-Received: Sat, 7-Sep-85 05:22:17 EDT
References: <253@argus.UUCP> <7000005@petrus.UUCP> <1345@hound.UUCP>
Reply-To: rdp@teddy.UUCP (Richard D. Pierce)
Organization: GenRad, Inc., Concord, Mass.
Lines: 107
Summary: 

In article <1345@hound.UUCP> rfg@hound.UUCP (R.GRANTGES) writes:
>[]
>What sort of data would you like, copp?
>Go take your spl meter to St. John the Devine and measure it
>yourself. Be sure to ask them to play only one note at a time
>as it might hurt your hearing standing 50 ft below the pipes
>or so.

Why do we insist on picking the pathological examples to illustrate
the norm?

>Perhaps you would like a Reference? Try Olson, Musical Engineering,
>first edition, page 231. Intensity Ranges of Musical Instruments.
>You will find a chart showing up to perhaps 110-115 db for organ at
>10 ft.

OK, let's see..

These SPL's were measured 10 ft away. Now, let's stand 50 feet away.
The intensity varies as the inverse square of the distance, so we have
a reduction in SPL of a factor of 25, etc. etc. Of course this do not take
into account absorbtion, etc.....

Then again, if Olson was talking 10 feet away from the pipes in the kind
of organ that he was measuring (large, enclosed Romantic beast), then the
SPL that actually reaches the floor is even less. Not much ever found there
way out of them things.

 Bass Drum and Kettle drum are similar. On pp. 205,206 there
>are some interesting and instructive plots of average pressure per
>cycle and peak to average ratios vs frequency for a wide variety
>of instruments, including 15 and 75 piece orchestras.
>
>Last, but not least, consider your own experience.  I assume you
>listen to music sometimes. Recall the occassions when a symphony
>orchestra going full tilt has been overwhelmed by a chord of
>full organ -or maybe less than full. If you don't listen to
>classical, try Saint Saens Symph No.3 Ormandy Telarc CD 80051
>Last movement should convince you that organs are loud.
>

Note in my previous posting, that I alluded to the fact that the instruments
Mr. Grantges refers to did not come into being until quite recently (last
100 years or less). There was almost no music written for combined organ
and orchestral music up until then. The most notable exception being the
Handel Organ Concertii. If we examine his organ at Great Packington, we find
it to be a small, quiet sedate, and, even compared to its contemporaries,
fairly quite. As a result, the total ensemble was small and relatively
quite. There were very, very few of the gargantuan instruments of the kind
that recent recordings of the likes of St. Saens have used in combination
with the gargantuan ensembles. Even Camille St. Saens own instrument (the
Cavaille-Cole organ in St. Sulpice) would cower under what Mr. Grantges
would consider the "average" organ.

AS an attempt at something other than conjectured proof, I have, at my
disposal, the specifications of some 1000 instruments scattered across
the Western Hemisphere. If anyone is interested, I might be coerced to
go through and see just exactly how many of these fit the mold that
Mr. Grantges is purporting to be the norm of organ size. So far, he has 
pointed to (I recall) only two specific instruments, the organ in St. John
the Divine and that in Riverside church.

Let's look through a Schwann catalog over the last decade and see what sort
of instruments the Complete organ works of the likes of Bach, Buxtehude,
Couperin, Dandrieau, D'Aquin, Frescobaldi, Sweelink, Bohm, Pachelbel, Handel
DeGrigny, Walther, Clerembaut, Byrd, Gibbons, Praetorius, Bruhn, Soler,
and even the likes of Cabezon are played on (there is a list of organ composers
that are, conservatively speaking, responsible for several thousand
individual and unique works!) Are they performed on the likes of the Atlantic
City Hall organ? No. How about St. John the Divine or Riverside? No, you
loose again. Well, what is typical for an instrument playing such works?
It seems such an instrument has 2 to 3 manuals, about 25 ranks, out of which
only 2 or 3 are reeds, and those are often things like Schalmei's or
Regals (which are REALLY quiet!). THey have relatively small mixtures (3-4
ranks) and they do fall well within the ranges I have previously described
for acoustic levels, even for "organo pleno". Note that organs (again, until
fairly recently) had stops which were very closely balanced in power output
but differed primarily in tonal color. The intent was to be able to (within
reasonable limits) be able to combine stop families into a cohesive, but
not overpowering, whole.

Further proof, if you so desire. I have access to the Aeolian-Skinner
organ in the Groton School. I have been in there, at the console, holding
a conversation in only slightly elevated tones whilst he played along "tutti">
There was no need to shout to be heard. The sound pressures simply weren't
that high, as my own extensive measurements have born out.

As an aside, exploring musical theory reveals why the organ-orchestra
(as well as most instruments used in ensemble with organs) are fairly
rare. Organs are forced to a fixed temperement, which in these less than
enlightened days, is almost always equal temperement, with the result that
there is almost no pure intonation possibilities (the octave being the sole
case). Orchestral instrumental players, whether they know it or not, (and
many don't seem to), tend to play there instruments in a modified just
intonation scheme, resulting in much purer chords and generally clearer
harmony. The two together tend to sound quite discordant. The problem didn't
effect Handel because his organs were tuned in a form of meantone temperement,
which might be considered a subset of just intonation.

>Next, lets consider the proposition: Broadly speaking, the nearest
>star (the sun) exhibits a tendency, when observed from earth to
>rise in the east. Bring data.

Sure thing, R., I'll have it there, first thing tomorrow morning. Be
up early, OK?

Dick Pierce