Klarinet Archive - Posting 000460.txt from 2001/02

From: Bill Hausmann <bhausmann1@-----.com>
Subj: Re: [kl] Difference Tones
Date: Mon, 12 Feb 2001 18:05:39 -0500

At 02:23 PM 2/12/2001 +0000, Tony Pay wrote:
>I know Bill Hausmann is worried about the organ stop that makes the
>walls of his church 'shake'. But whatever the explanation of this is,
>it can't be due to the production of a lower frequency *perception* by
>the addition of a higher pipe (as was sometimes done in early pipe
>organs).
>
>Perhaps his organ uses a more modern technique. An electronic device
>called a ring modulator produces real sum and difference tones from two
>inputs, but I don't know whether that technique is ever used in organs.
>
>In order to have any idea at all, I want to know more about the
>'shaking'. Is it a space resonance on certain notes, or noticeable at
>all pitches? How do you detect it, Bill, with your hand?

I only know about this organ from a recording. But you can check it out
yourself more easily than I can, Tony. The recording was made in Liverpool
Cathedral! The 16 Hz 32-foot CCCC, in combination with another pipe a 5th
above it produces a resultant bass note that can be measured, recorded,
seen on an oscilloscope, and FELT as a 8 Hz 64-foot CCCCC. The waves in
the grooves on the LP disc (recorded digitally, but cut on an analog disc
in 1979) on a separate sample 8 Hz CCCCC can be clearly SEEN on the vinyl
with the naked eye. That's why I am having so much trouble with this
"perception" thing, even though I doubt that my stereo does the recording
any justice at all.

Bill Hausmann bhausmann1@-----.com
451 Old Orchard Drive http://homepages.go.com/~zoot14/zoot14.html
Essexville, MI 48732 ICQ UIN 4862265

If you have to mic a saxophone, the rest of the band is TOO LOUD!

---------------------------------------------------------------------
Unsubscribe from Klarinet, e-mail: klarinet-unsubscribe@-----.org
Subscribe to the Digest: klarinet-digest-subscribe@-----.org
Additional commands: klarinet-help@-----.org
Other problems: klarinet-owner@-----.org