DIYAPASON-L Digest #472 - Tuesday, December 25, 2001
 
hi
  by "Gary Black" <gblack@ocslink.com>
Re: [Residence Organs]  Springs and Weights
  by "Ron Rarick" <ronrarick@mindspring.com>
Re: [Residence Organs]  Springs and Weights
  by "Mike Gettelman" <mike3247@earthlink.net>
 

(back) Subject: hi From: "Gary Black" <gblack@ocslink.com> Date: Mon, 17 Dec 2001 04:00:04 -0600   HI Folks, I am refiguring my computer and so would you please reply with an e-mail back to me so that I can keep you in my address book. Happy Holidays and thanks. Gary Black      
(back) Subject: Re: [Residence Organs] Springs and Weights From: "Ron Rarick" <ronrarick@mindspring.com> Date: Tue, 25 Dec 2001 20:47:18 -0500   I may have missed it, but I don't remember anyone mentioning a major advantage of using weights as well as springs: the wind pressure can be far more easily fine-tuned. Springs are pretty crude in this regard, but if you want to "bump" the wind pressure up or down just a smidgen (forgive the highly technical organ building jargon) there's nothing easier than tossing on another brick or removing the two1928 hymnals that somebody put on the reservoir in 1961. Sometimes this sort of common-sense practicality in the field comes first and the theories follow later.   Ron Rarick Muncie Indiana   > DIYAPASON-L: a Discussion list for owners and builders of their own > Residence Pipe Organs. > HOMEPAGE : http://www.diyapason.pipechat.org > List: mailto:DIYAPASON-L@pipechat.org > Administration: mailto:owner-DIYAPASON@pipechat.org >    
(back) Subject: Re: [Residence Organs] Springs and Weights From: "Mike Gettelman" <mike3247@earthlink.net> Date: Tue, 25 Dec 2001 21:20:57 -0500   Ron Rarick wrote:   > I may have missed it, but I don't remember anyone > mentioning a major advantage of using weights as > well as springs: the wind pressure can be far more > easily fine-tuned.       Merry Christmas Ron, Wow, not only did you miss It, but It came from one of our more savvy pro organ builders. Tim Bovard treated us to a short lesson on this subject last Friday that made more sense to me than Audsley, Barnes, and all my other organ building books combined. I believe it's worth reprinting just for you.   Subject: [Residence Organs] Springs and Weights Date: Fri, 21 Dec 2001 16:59:29 -0600 From: Tim Bovard <tmbovard@earthlink.net>   Hi, Craig!   Springs (coil or compass) on a reservior provide a quick response to a demand for wind. They provide most of the energy to move the reservior top/valve in response to any variation in pressure. Weights on a reservior serve to add *inertia* to the reservior top, once it is in motion (caused   by the spring's reaction to a demand for wind). The weight tends to make   the reservior top/valve overcorrect *very slightly*, which can create a subtle effect in response to sudden demands for wind (i.e., a "big chord"). The end result of a good marriage of the two becomes a wind supply that is most nearly rock-steady, but not quite. A little "give" will be apparent   under certain playing conditions where it is appropriate. Think of the end of the Widor Toccata -- during all the running arpeggios and etc, the wind remains steady, for it is seeing a relatively steady, constant demand. But for those last two chords (dah-DAHHHHHHHHHHH), seperated by a brief rest,   the extra inertia of the weighted reservior top gives the final of those two chords just a *squooch* of extra emphasis, as it slightly overreacts to the wind demand variations produced by the rest. The overall result is that the music gains a natural "life" of its own, in much the same way as a human voice is capable of slightly emphasising any given syllable of sound it produces. [NOTE: I am in no way suggesting/endorsing "wiggle wind"...the effect I speak of is truly so subtle so as to be unnoticeable   by itself. You couldn't particularly *hear* the effect, but you would likely notice the *absence* of it.]   One common criticism of schwimmer-style wind regulators is their lack of this "inertia effect" -- no part of the schwimmer mechanism has the inherent mass to be able to react so imprecisely to the variations in wind demand. Schwimmer wind is so nearly completely "rock-steady" that the music can border on becoming "sterile" (a term/concept often used to bash   the sounds of electronic organs).   It would seem that weights on typical reservoirs serve to *add* a bit of error factor to the wind regulation system -- but a *desirable* error factor. Also worth remembering is the fact that the reservoir top has its own amount of "mass" even before the addition of weights...in some instances extra weights are not needed.   Weights on reservoirs will also affect the tremolo's action on that reservoir, but that's a whole 'nother topic for a different time. <g>   There wouldn't seem to be any finite "formula" for what will *always* be the best...as each organ is different, such are the characteristics of its winding system. The trick becomes finding the correct balance for each one. Fortunately, "trial and error" is usually a quick and efficient means to this end!   Hope some of this made a *little* sense...<G>   Cheers all --   Tim Bovard Little Rock AR