Adding toe studs to an Allen ADC-4500

[Admin]

I don't know, what I can say from experience is that it is not common for the Pedal Division toe studs to be independent of the Pedal Division pistons.

On the Allens I'm familiar with, there only studs for the pedal division, no divisional pistons.

[Leisesturm]

On the Allens I'm familiar with, there only studs for the pedal division, no divisional pistons.

Ah...interesting. I play mainly pipe organs. Almost always you have Pedal Division pistons to the left of the Great (or Choir if it is a 3 or more manual console) Divisionals. Most digitals I have played have not had any toe pistons at all. Those that did have them were Rodgers instruments that I played rather infrequently and paid much more attention to how many General toe studs were available . Only rather recently have I extended my technique to the point of programming Pedal Divisionals for use in performance. I was forced to this out of necessity since the instrument I am playing has zero memory levels. Agh. It's been quite the learning curve.

[samibe]

Thanks again Admin.

I'll check on how the accomp and pedal were combined and report back.

Sam

[KOC62]

The reason I was asking is because our Johannus Opus 1100 church organ has added (i.e not original) toe switches for SW-GR, GR-PED and SW-PED. On the console the same name switches are also there. I haven't verified the wiring but suspect they're wired in parallel. Hence the question of how a visiting organist would use them if it's not a conventional way to wire them this way. How else would it be done if the organ has no other place to detect the toe switches?

[myorgan]

You don't. The first time you hit the toe stud for Pedal Divisional 2 expecting the same combination that you set earlier on Pedal Divisional 2 on the piston under the Great manual you will know that the inputs to the combination action are not simply paralleled, but independent. As for conventions, I don't know, what I can say from experience is that it is not common for the Pedal Division toe studs to be independent of the Pedal Division pistons. Not on Classical style consoles that is, the 'convention' for Theater style consoles may be different.

AFIK, all Pedal Divisional pistons are separate from the Great. I know on some of Allen's earlier MOS organs, the Pedal Divisional Pistons were to the right of the Swell Divisional Pistons. Then came the toe studs, which were never duplicated on the manuals, as far as I know.

On the Allens I'm familiar with, there only studs for the pedal division, no divisional pistons.

I think what brought this up is that the OP is going to add toe studs, but if I recall correctly, he has a self-contained console (the ADC-4600 manual is here: https://www.allenorgan.com/www/suppo...C3600-4600.pdf, but there is no ADC-4500 manual that I can find.). I've never known Allen to have toe studs for the self-contained consoles until they added them on the most recent technology and raised the speakers up a bit above the pedals to accommodate the change (see the current Chancel line here: https://www.allenorgan.com/www/produ...17a/cf17a.html).

I'm sure I'm wrong, but I hope that helps people find the information they need.

Michael

P.S. The ADC-4600 indicates it can have MIDI, so I'm not sure where you stand there. Probably Admin's product would work best for you.

[Leisesturm]

AFIK, all Pedal Divisional pistons are separate from the Great.

Absolutely. On the organ I play now and the two before it, and any others I can think of there were literally two sets of Divisionals side by side, on the Great keyboard. A set to the left for the Pedals and the set located centrally for the Great. The Generals were split on either side of the Swell Divisionals. The toe studs duplicated the Generals, four on one side of the expression shoes, and four on the other side, and the Pedal studs just above them split the same way. If you set a Pedal piston, you could be fairly sure that the same numbered toe stud would give you the same combination. Only the organ I play now differs. If you set a piston on the Pedal Division on the Great Keyboard the toe studs can have entirely different combinations set on them. You could have 16 unique Pedal Division presets, way too many; IMO its the Generals that could use that kind of flexibility!!!

[samibe]

Project update:
I removed the speaker cover screen to see how much room there is for toe stud rails. The knee board has been finished really well. It is a bit sun-bleached so it looks like it has tan lines.

I've decided that I like how the organ looks without the speaker cover. So, after I get the stud rails made and installed, I'm going to make individual black speaker covers just to protect the speakers.
So far I've made the stud rails out of poplar and cut them into an Allen-esque shape. I've laid out the pistons and I can get 15 pistons to fit on one row (8 on the left and 7 on the right). I am going to start with 10 pistons (5 on each side) but place them so that I can add more later. I am currently working on covering the poplar with a 1/16" thick walnut veneer.

The stud rails will cover about 5/8" of the woofer on the right and about 1/4" of the two lower speakers on the left. It shouldn't affect the sound too much (I hope). We'll see how far I can get this weekend.

[myorgan]

The stud rails will cover about 5/8" of the woofer on the right and about 1/4" of the two lower speakers on the left. It shouldn't affect the sound too much (I hope). We'll see how far I can get this weekend.

Sam,

Forgive me for stating the obvious, but be sure your toe studs on the far left and right do not go too far over the pedals. In other words, account for the extra distance the toe studs will stick out past the wooden rail. Otherwise, you'll accidentally hit them on the way by--and that's not necessarily a good thing.

Also, when extending the wooden rail over the speaker enclosure, make sure your rail doesn't impede the excursion of the speaker surround when fully extended. That could possibly result in distortion.

Michael

[samibe]

Michael,

Thanks for helping me see what I should watch out for. I think I will only have enough time this weekend to get the stud rails finished and the toe studs mounted (no wiring yet). I figure that I can try them out and if they are sticking out too far, then I can remove some wood from the back of the rails. If they aren't sticking out enough, then I can add some spacers to the back. Although, I'm pretty sure I have them positioned on the too-far-out side of about right.

As far as the speakers are concerned, they are mounted to the back of the knee-board. I don't think any of them have 3/4" excursion, but I will verify that. If I find issues while experimenting with the toe stud position then I can make some room for the speakers. I also want to check if the mid-range speakers are significantly affected by the rails partially covering them. We'll see how it goes. I'll post some pictures when I get everything in.

[myorgan]

Michael, thanks for helping me see what I should watch out for. I think I will only have enough time this weekend to get the stud rails finished and the toe studs mounted (no wiring yet). I figure that I can try them out and if they are sticking out too far, then I can remove some wood from the back of the rails. If they aren't sticking out enough, then I can add some spacers to the back. Although, I'm pretty sure I have them positioned on the too-far-out side of about right.As far as the speakers are concerned, they are mounted to the back of the knee-board. I don't think any of them have 3/4" excursion, but I will verify that. If I find issues while experimenting with the toe stud position then I can make some room for the speakers. I also want to check if the mid-range speakers are significantly affected by the rails partially covering them. We'll see how it goes. I'll post some pictures when I get everything in.

Sam,

Make sure the hole you drill through the toe stud board is large enough for the wires to go through. You will want to either make sure the toe stud wires currently connected are long enough to go through the mounting board, or not mount the studs until you have the wires soldered. You'll notice on my thread, I soldered the toe studs and verified they worked before screwing them on.

Regarding the speakers, there is a quick way to check. The woofers are the only ones that might have enough excursion to be affected, and to test them you can briefly place a 9v battery across the terminals of the woofer ONLY (not mid or tweeter). You will need to have someone help you test the woofer. Make sure the organ is off.

Also, please wait for the experts to weigh in before you test the speaker using this method. I want to make sure you don't damage any circuits inside the organ by doing it. I've only tested external speakers when they were unhooked--never connected.

Hope this helps a little more.

Michael

P.S. On some recent organs I've seen, Allen only has the mounting board on the far end of the toe stud rail, and then 1 or 2 are mounted to the face of the organ, closer to the center. Don't know if that's an option or not.

[samibe]

I'm planning on routing a slot in the back of the toe stud rails and running all of the toe stud wires in it and through a single hole in the kneeboard. I'm considering running wires from the relay/DM board through the knee board and then soldering to toe studs to those once they are mounted. I pre-drilled the holes for the wires before I put the veneer on the rails.
Here are some pictures before I painted the rails,

After they were finished,

and with them resting on the pedalboard. They match the rest of the organ (except that the finish is older and has yellowed a bit on the organ).

I didn't have as much time to work on it this weekend as I thought. So, I didn't get the rails and toe studs mounted to the kneeboard. Next time I get to work on it, I should be able to get everything mounted and ready to solder.

[samibe]

I had a chance to work on my organ again last weekend. I routed a slot into the back of the toe stud rails that will give me some flexibility when it comes to running the wires from the studs to the relay/DM board. I mounted the toe studs to the rails and mounted the rails to the organ. The picture also shows the rings for the new speaker covers I made. The speaker covers were finished and mounted, but I forgot to take a picture of it. Eventually, I will add two more studs on the right and three more on the left. I did some practicing to make sure the toe studs are not in the way of the pedals. They definitely were not in the way, but I almost wish they were a half inch higher on the kneeboard or a quarter inch further out. I may tweak the studrails' position a little bit the next time I get to work on my organ.


I did some more searching around the organ and found the relay(?) board that seems to have the signal from the Acc/Ped pistons split to the Acc and Ped input on the DM board. The thicker dark blue wire should be the signal from the Acc/Ped pistons. Attached to the Acc/Ped pegs are some yellow and red wires that seem to run to the DM board.

Attached to the Solo pins are some thin blue wires and attached to the Great pins are some thin green wires. If I'm understanding the third picture correctly,
Red: 5, 6, 13, 14, 21, and 22
Green (Great?): 7, 8, 15, 16, 23, and 24
Blue (Solo?): 9, 10, 17, 18, 25, and 26
Yellow: 11, 12, 19, 20, 27, and 28
and I just need to figure out if Red controls the Pedal stops or if Yellow does. Then it should be a matter of running the toe stud leads to the Ped pins, clipping or unsoldering the pedal wires, and extending/soldering them to the Ped pins.

To figure out which wire controls which division I could set a divisional preset (with both Ped and Acc stops), press cancel, turn off the organ, unsolder one wire from that preset (yellow) and insulate the end, turn the organ back on, hit the preset and see which tabs are activated? If the Acc tabs are activated, then I would know that the Yellow wires run the Pedal division. If the Ped tabs are activated then I would know that the Red wires control the Pedal division. Are there any issues with this test that I missed?

Admin, it's interesting that Allen seems to have wired the pistons to the J80 connector exactly opposite of your description in post #14. Why would they have done that? Is it just that the actual order is less critical than keeping every division separate?

[Admin]

Attached to the Solo pins are some thin blue wires and attached to the Great pins are some thin green wires. If I'm understanding the third picture correctly,
Red: 5, 6, 13, 14, 21, and 22
Green (Great?): 7, 8, 15, 16, 23, and 24
Blue (Solo?): 9, 10, 17, 18, 25, and 26
Yellow: 11, 12, 19, 20, 27, and 28
and I just need to figure out if Red controls the Pedal stops or if Yellow does. Then it should be a matter of running the toe stud leads to the Ped pins, clipping or unsoldering the pedal wires, and extending/soldering them to the Ped pins.

To figure out which wire controls which division I could set a divisional preset (with both Ped and Acc stops), press cancel, turn off the organ, unsolder one wire from that preset (yellow) and insulate the end, turn the organ back on, hit the preset and see which tabs are activated? If the Acc tabs are activated, then I would know that the Yellow wires run the Pedal division. If the Ped tabs are activated then I would know that the Red wires control the Pedal division. Are there any issues with this test that I missed?

Admin, it's interesting that Allen seems to have wired the pistons to the J80 connector exactly opposite of your description in post #14. Why would they have done that? Is it just that the actual order is less critical than keeping every division separate?

According to my diagram your

Red wire pins: Swell
Green wire pins: Choir
Blue wire pins: Pedal
Yellow wire pins: Great

Wire colors don't appear on the diagram, only pin numbers, so this mapping is based on the pin numbers and their respective wire colors as provided by you.

Allen may have used different mappings for two manual organs. On my three manual theatre model

Great = Great
Acc = Choir
Solo = Swell
Ped = Ped

[samibe]

Admin, thanks for your mapping description. I still need to double check wire locations and circuits with my multimeter. If it turns out that the wire and pin order on my organ is different than your diagram, would that be an issue? or would it still function the same as long as the input pins map to the corresponding output plug? (divisional pins 5, 6, 13, 14, 21, and 22 (on J80) map to stop control plug J8(?) on the DM board which controls the same division's stops)

[Admin]

If it turns out that the wire and pin order on my organ is different than your diagram, would that be an issue? or would it still function the same as long as the input pins map to the corresponding output plug? (divisional pins 5, 6, 13, 14, 21, and 22 (on J80) map to stop control plug J8(?) on the DM board which controls the same division's stops)

Right. Each of the output connectors is dedicated to one division in the standard configuration.

Again, on my model (determined empirically):

J81 - Pedal
J82 - Accomp
J83 - Great
J84 - Solo