DIYAPASON-L Digest #648 - Monday, September 16, 2002
 
Re: [Residence Organs]  Suspended bass notes on celing?
  by "Mac Hayes" <mach37@mindspring.com>
Switching
  by "Larry Chace" <RLC1@etnainstruments.com>
Re: [Residence Organs]  Organ Pictures
  by "Mike Blackwell" <mblackwell@wallace.com>
Devtronics
  by <Kzimmer0817@aol.com>
Windy question
  by <Pipewheezr@aol.com>
Devtronics WEB site
  by "Forrest Radley" <xyzzy@budget.net>
Re: [Residence Organs]  Windy question
  by "Richard Schneider" <arpschneider@starband.net>
Re: [Residence Organs]  Devtronics WEB site
  by "Mac Hayes" <mach37@mindspring.com>
 

(back) Subject: Re: [Residence Organs] Suspended bass notes on celing? From: "Mac Hayes" <mach37@mindspring.com> Date: Mon, 16 Sep 2002 03:50:01 -0700   GEU30CG@aol.com wrote: > ... > Option 2) Lay the notes all on their sides stacked. Again a great > option but the chest the notes rest on is just over 9 feet long, so > it won't fit either. ...     I have exactly the same problem. My solution is to stack the bourdons, and mount the 9' chest on the wall, angled so as to fit under the 8' ceiling. I will still need to use about 18" of tubing for each pipe- easier than trying to fit the feet in the toe holes snugly enough to prevent air leaks, not to mention mounting problems if I *don't* attach the chest to the wall. Since I live in earthquake country I am bracing the bourdons securely. I have a picture I can attach to email if you want to see how I am doing this.   Mac Hayes Rosamond, CA  
(back) Subject: Switching From: "Larry Chace" <RLC1@etnainstruments.com> Date: Mon, 16 Sep 2002 11:05:39 -0400   At the risk of adding confusion rather than illumination, I'll try to make some comments about "switching". In order for the "ASCII art" diagrams to make any sense, you must use a fixed-space font, not a proportional font. I'll put at least some character in column 1 of each line because I know that some e-mail programs are "too smart" and will shift things that start with a blank.   1. GENERAL PRINCIPLE   Each thing that makes sound needs to have at least two controls, operating in series. One is the key on a keyboard and the second is the "stop" (whether tab or knob or button).   On a tracker organ, the key operates a valve letting air into a "note channel" that runs under all of the pipes for that key. The individual = air paths from that channel up into the pipe feet are interrupted by sliders that move at right angles to the note channels and are pierced so that in one position they block all of the air paths for a given rank and in the other position they open all of the air channels for that rank. The note channel valve must be open and the slider must be "open" in order for the pipe to sound.   This same principle applies to pneumatic and electric switching, even if the "circuit diagrams" appear to be different. (It also applies to the brilliant *mechanical* switching used by the Austin company.)   2. ELECTRIC SWITCHING   Here is the wiring for a single manual key ("K") that can operate any of three stops ("S1", "S2", and "S3"). The switch contacts are shown as "/." ("flatten the slash to a dash" when closing the contact!) The pipe = magnets are shown as "$" (a coil of wire around an iron core!), and there are 3 pipes ("P1", "P2", and "P3"). Each "*" is a position on a terminal strip ("junction board" in organ terms).   .. +12v .. | K S1 P1 .. +-----/.-----/.--*--$--Gnd .. | : .. | : S2 P2 .. +-----/.-----/.--*--$--Gnd .. | : .. | : S3 P3 .. +-----/.-----/.--*--$--Gnd   The manual key "K" has three SPST (normally open) contacts, which all move in parallel when the key is pressed, and each one connects its output wire with the + side of the DC power supply. This is like the pallet valve and note channel on a tracker chest (including the borings that run up to the sliders).   Switches "Sn" are actually 61PST (normally open) switches, and if this sheet of (virtual) paper represents this one note "K", then there are 60 other sheets, parallel to this one, containing the other 60 notes. All of the "S1" contacts will move at the same time, when the "S1" stoptab or stopknob is turned on. This is like the slider on a tracker chest, and once again it is at "right angles" to the key switches.   In order to play a pipe, you have to turn on its key and its stop; either switch, when open, will block the flow of electricity to the magnet.   3. UNIFICATION   If you want to play a given pipe from two different places, then you can connect wiring to the junction boards (shown by "*" above).   .. +12v .. | K S1 P1 .. +-----/.-----/.--*--$--Gnd .. | : | .. | : S2 P2 .. +-----/.-----/.--*--$--Gnd .. | : | .. | : S3 P3 .. +-----/.-----/.--*--$--Gnd .. | | .. | L S4 | .. +-----/.-----/.--+   In this case, I've shown another key ("L", perhaps an octave above "K") = and another stopswitch ("S4"). This stuff is actually on a different sheet of (virtual) paper, the one corresponding to key L. The output of the stopswitch for this note runs back to the magnet for P3 (on the K sheet of paper). Now, you can play P3 from key K and stop S3 as well as from key L and stop S4. Neither key can interfere with the other because there are now *four* contacts under each key. (Other keys will connect via their S4 contacts to the other junctions so that they can play the other pipes.)   3. NOTE RELAYS   For larger instruments, or where there are inter-manual couplers, this scheme is modified by having "note relays" that are just like the key contacts except that an electro-magnet (rather than a finger) presses the contacts together. Now you can add an extra level of switching to this diagram, in which the pipe magnets are really the magnets on the note relays and the stopswitches are really couplers. An additional set of stopswitches will connect to the output of the note relays, and that is what will finally drive the pipe magnets.   This method of switching was devised before diodes were available and depends upon all of the individual contacts as a means of preventing loop-backs and other situations in which unwanted pipes get played. The individual contacts at the key or at the note relay serve to energize the individual circuits *and* to prevent loop-backs.   4. OTHER METHODS   The schemes shown above all assume pretty old technology, simple = open/close switch contacts. As long as you replicate the same over-all logic, you = can implement this sort of switching in all sorts of ways. Using modern devices such as diodes and power transistors, you can sometimes avoid the 61-pole switches; just be careful that electric current (like wind) = doesn't end up flowing "backwards" into unwanted places; if it does, you'll hear the results!   Some integrated circuits can be used to implement the switching, but just remember that you need to have enough of them to cover the entire specification and not just a single note's wiring diagram! For those who want to "roll their own", let me suggest a particular device, the UDN2987A from Allegro. It is an 8PST switch with an "open emitter" design (its outputs are either high or floating) and it has an active-high enable input. This chip can even drive magnets (small ones), and it is protected against short-circuits. It will run on normal organ DC (poorly-regulated "12" volts). It costs about $2 each. Eight of them would make up a 64PST stopswitch, and you can gang their outputs together by just connecting = them with wire or a circuit board trace. Unfortunately, these devices are not carried by the electronic "hobbyist" supply houses, nor are they made by any other company.   If you don't like those chips, the old 4000-series CMOS is still being = made and it will run on normal organ voltages. However, its outputs are very weak and you need driver chips or power tranistors to fire the magnets.   For a small instrument without "modern" things like MIDI, the old = switching schemes are fine, assuming that the switch contacts are in usable condition. For one thing, you can look at them and see how they work, perhaps tracing out some circuits with a buzzer or volt meter. Even simpler are the keyboard-mounted switches used by Moller and others in which the key contacts and stop switches are all in one unit, with little sliders that move the contacts away from the contact bars that the keys move.   I would not recommend buying new components to build such a relay, since the cost of the components is considerable and the amount of wiring necessary is substantial. Using such components to add a stop or coupler or two can make sense.   As Rich Schneinder stated so very nicely, the companies that sell organ relay systems have invested a lot of time and money to develop their products, and that is reflected in the prices. As amateur builders, it is often possible to invest one's time (rather than one's money), and that = can also be fun and very satisfying. Professional organ builders work under a different set of constraints!   Larry Chace      
(back) Subject: Re: [Residence Organs] Organ Pictures From: "Mike Blackwell" <mblackwell@wallace.com> Date: 16 Sep 2002 10:31:30 -0500   Sure. I have an Austin console. Unfortunately the chests were destroyed or reused before I got there, and the remaining pipework was a couple of large romantic stops that would not have worked well for a home organ.   Mike   On Fri, 2002-09-13 at 18:22, Kzimmer0817@aol.com wrote: > List, > > I have three zip files that unzip into about 6-7 pictures of the Austin > organ I just acquired. I don't know if anybody is interested, but I > will be happy to send them to anybody who would like to see them. They > were taken by the guy who was selling the organ. > > Thanks, > Keith Zimmerman      
(back) Subject: Devtronics From: <Kzimmer0817@aol.com> Date: Mon, 16 Sep 2002 19:07:54 EDT     --part1_e5.1df72d18.2ab7be4a_boundary Content-Type: text/plain; charset=3D"US-ASCII" Content-Transfer-Encoding: 7bit   Does Devtronics have a website?   Thanks, Keith   --part1_e5.1df72d18.2ab7be4a_boundary Content-Type: text/html; charset=3D"US-ASCII" Content-Transfer-Encoding: 7bit   <HTML><FONT FACE=3Darial,helvetica><FONT SIZE=3D2 FAMILY=3D"SANSSERIF" = FACE=3D"Arial" LANG=3D"0">Does Devtronics have a website?<BR> <BR> Thanks,<BR> Keith</FONT></HTML>   --part1_e5.1df72d18.2ab7be4a_boundary--  
(back) Subject: Windy question From: <Pipewheezr@aol.com> Date: Mon, 16 Sep 2002 20:58:03 EDT   Happy Monday night. I have a chest dilemma, I am working on the first four rank choir chest. = The question is there are tow ranks that need 6" w.p. and two ranks that need = no more than 3.5" w.p. The lay out makes this grouping a must. Do I have a problem? Thanks Dennis  
(back) Subject: Devtronics WEB site From: "Forrest Radley" <xyzzy@budget.net> Date: Mon, 16 Sep 2002 18:32:18 -0700   <excerpt>Keith asked, <fontfamily><param>Arial</param><smaller>Does Devtronics have a website?   </smaller></fontfamily></excerpt>   The answer to that is, "well, sort of." If you go to the following:     http://www.classical-devtronix.com     you will see the site which is still under construction. It has been that way for over a year, I think. However, the Devtronix catalog in ..pdf form is there. The site just doesn't have handy button for you to "click" on. To view the catalog go to the following:     http://www.classical-devtronix.com/catalog/catalog.pdf     There you will find a catalog which is about 100 pages long. If you are on a slow speed phone line, it will take a while.     Happy hunting.     Forrest  
(back) Subject: Re: [Residence Organs] Windy question From: "Richard Schneider" <arpschneider@starband.net> Date: Mon, 16 Sep 2002 20:41:21 -0500     Pipewheezr@aol.com wrote:   > The question is there are tow [sic] ranks that need 6" w.p. and two = ranks that need no > more than 3.5" w.p. The lay out makes this grouping a must. Do I have > = a problem?   Depends on what the ranks in question are. If the ones requiring 6" are reeds, the you'd have a bit of a problem.   Nothing in a house should be on 6". Ever. Unless it is a castle!   More details please?   -- Richard Schneider, PRES/CEO SCHNEIDER PIPE ORGANS, Inc. Pipe Organ Builders 41-43 Johnston St./P.O. Box 137 Kenney, IL 61749-0137 (217) 944-2454 VOX (217) 944-2527 FAX mailto:arp@schneiderpipeorgans.com SHOP EMAIL mailto:arp@starband.net SHOP SATELLITE EMAIL mailto:arpschneider@starband.net HOME OFFICE EMAIL http://www.schneiderpipeorgans.com WEB PAGE URL      
(back) Subject: Re: [Residence Organs] Devtronics WEB site From: "Mac Hayes" <mach37@mindspring.com> Date: Mon, 16 Sep 2002 18:59:25 -0700   Forrest Radley wrote: > > Keith asked, Does Devtronics have a website? > > The answer to that is, "well, sort of." If you go to the following: > > http://www.classical-devtronix.com > > you will see the site which is still under construction. ...     But, they respond quickly to email, so maybe they just don't waste as much time on the internet as I (and maybe a few others) do.   Mac Hayes