Recommendations for Allen Organ, C3 tube Amp, and Gyrophonic speaker

[Jarrettbconner]

I’ve e recently acquired a classic Allen Organ from a nearby church.

The speaker and organ were disconnected (wires severed) when it was removed from the church.

it’s now in my barn and I’m looking to get it back in action as a practice instrument.

I am new to the organ and tube amps, so any (and basic) recommendations are welcomes.

any thoughts on how to approach this?

I’ll add pictures below.

[myorgan]

I’ve e recently acquired a classic Allen Organ from a nearby church.

Mr. Conner,

From what you posted, I suspect you have acquired an analog Allen organ. Our resident "expert" on those organs would be Silken Path (Lamar), as he has at least two TC-4 organs he has either restored or scavenged for parts. It would help if you could find the builder's plate (with the Patent Numbers on it) and tell us the model organ you have. That's the quickest way for us to help you.

Could C3 Custom be the model of the organ? Allen did make one. Pictures are great. Normally they cannot be posted until you're off moderation status, but try anyway–the Forum limits us to 5 pictures/post, and under a certain dimension/filesize.

Welcome to the Forum, and I look forward to learning more about your restoration project.

Michael

[Jarrettbconner]

Thanks!

Allen C1 4669 is what shows on the plate.

I’ve tried to post a few photos here of the inside of the speaker and the organ (closed up).

[Jarrettbconner]

Couple more pictures

[Silken Path]

Hi, Jarrett. Welcome to the forum. That organ is a little older than what I have ('59 and '67), but I can see the family resemblance in the photos.

Tube amps operate at high voltages. These voltages come from transformers that step up house current to the voltages needed by the tubes. These voltages can literally stop your heart. Please don't go poking around in those circuit boxes until you know what you're looking for (and have some basic tools).

I think one way to proceed is to examine where the wires were cut. Are the wires inside the sheath color coded? If so, that will make it easier to reconnect than having to figure out where everything goes at plugs and terminals.

I think I would work on that first and then find out if the amps will come up.

Have you heard this organ work? Where you present for the removal?

And something I'm curious about -- if you depress a key and look at the keys beside it, do you see all plastic, or plastic and wood? My '59 has those wood keys, and they are warm and nice to play on and just as precise as the wooden stick and plastic blob keys my '67 has.

[Silken Path]

Jarrett, there's a real good safety advice "sticky" at the top of this section.

https://organforum.com/forums/forum/...binets-leslies

[Jarrettbconner]

Silken Path I haven’t heard it work but was told that it did work before it was removed. I wasn’t there for the removal. I’ll grab some more
Pictures of the wires and the inside of the organ soon. Thanks so much for the advice (esp. re safety!).

[Silken Path]

I think if you peel the wires back a little (I've actually slit more than one with an old steak knife), you'll be able to see the individual wires and hopefully find what they connect to in other wires. There may be two wire bundles going to the gyro, and it looks as if that's an amp in there, so it may be three or more. I don't know where the voltage came from for the oscillators and for keying in the tube models, but if we're lucky, we won't need to know before you get to hear it.

Is that the main wire bundle I see partially under it?

[Jarrettbconner]

Yes, wooden keys.
also some wooden components under the hood. Looks delicate!

And. So. Many. Tubes in the organ itself.

yes the speaker also has its own tube amp as well.

im attaching a few more pictures.

included are the wires. There are four wire sheaths coming out of the organ (plus an intact power cable/plug).

thanks for any insights!

[Jarrettbconner]

A few photos of the Amp/gyrophonic set up.

[Silken Path]

The connectors just below the two gain controls are the inputs, apparently, from the organ. Look at the wires coming from the oscillator banks on the back of the organ and see where they go. I'm guessing that they go to the PEDAL and then out to the amps. They might go to a preamp and THEN out to the amps, and that may be your four conductor wire.

Do you have a cable with a four-way-female plug that looks like the round male plug in the gyro?

Also, what are the gyro control tabs labeled as? My TC-4 has GYRO OFF, and FLUTE TREMOLO.

Also, do all the outside cables go to that terminal strip?

[Silken Path]

What I'm thinking now is that in the gyro is the main power amp (right) and the gyro control box (left). The wiring to the gyro is internally connected, and the terminal strip on the amp goes to the big panel speaker.

By the way, those selenium rectifiers -- that row of squares - can shock you if power is present and you brush against one. Found that out in my gyro. :)

Do you have a voltmeter? (We can experiment to find what the (floor) terminals are if need be.)

Also, what voices does this organ have? Flutes, diapasons, reeds? (Gyros usually are on flutes. Diapasons sound funny with tremolo.)

[Silken Path]

With a bit more study of your pictures... That big box on the floor of the organ provides the low "B+" keying voltage (what actually activates to push the power onward) and filament (high) voltage - maybe 400 to 600 volts or more. I don't know.

That top row is 14 diapason generators and second and partial rows are 16 flute generators. The extra flute tones are involved in the "synthesis" stops - made up stops like harps and bells.

That ominous-looking affair viewed from the top is just the crank springs. When you press a key, the crank rotates to make contact. It's not as complicated as it looks and it's incredibly reliable.

All cool so far. Jarrett I'm anticipating that you're going to tell us that all those four cables go to that terminal strip on the organ floor. We shall then rejoice, because we can figure out what these are by playing with the switches and stops and looking where they go on the opposite end (inside the gyro).

[John Vanderlee]

technical correction:" filament (high) voltage - maybe 400 to 600 volts or more." should be "plate high voltage...." the filament runs on 6 or 12 Vac depending on the tube tube - probably 12volts for 12AU7 tubes.

[Jarrettbconner]

Awesome! Thanks for all that analysis.

No female plug for that, unfortunately.

the wires do go to the base of the organ. Seems like two go to the pedal and two to the amp(?).

almost time to rejoice?

unforunately there are no cut wires coming out of the speaker so there is nothing to match. I will peels those sheaths apart soon to see what we are dealing with.

additional pictures attached.

more to come!
thanks again!

[Jarrettbconner]

Here is the speaker side input spots.

I need to connect something to that “switch” port somehow.

I need to connect to those “input” ports as well.

Not sure what to connect where yet or what else may need to be connected.

The speaker does have power. When I plug it in the tubes start to glow.

[Organkeys Jones]

The "switch" socket in the gyro is for that console lever in one of your photos labeled "Gyrophonic - Off - Celeste". That is basically fast (tremolo), off, & slow. Did you say that round plug was missing? A replacement can probably be found.

The only other two connections are the audio, "Input #1 and Input #2". Those would be the flute and diapason generators, and the cables are connected to terminals on the console floor as pictured. If the screw on connectors (very old style!) are missing, I would remove the ones in the amp and replace them (RCA maybe).

Was there an AC (110 volt) cable coming from the console to the Gyro? Or did you just use an extension cord to power up the gyro? You have just one gyro, right?

To be honest, the only thing of value in that organ is the tube amp!

[Jarrettbconner]

Thanks for the notes!
Hopefully it will be of some value to us once it’s up running!

[Jarrettbconner]

Gyro and Organ plug in independently.

I ordered a couple switchcraft 2501F connectors to be able to use those old input ports, rather than cracking open the amp at this point. I'm sure that is the best thing to do, but I'm such a novice, I want to get it running with the fewest interventions possible at this point. Then I'll dive into more serious rehab down the road.

[Silken Path]

Thanks, Jarrett. The two wires going to the amps either directly or indirectly go to the PEDAL. These will be SMALLER two-conductor wires. I don't know WHAT that connector for the amp inputs is, but like Organkeys Jones says we can certainly update the fasteners. Note also that the audio will work even if the gyro control is not attached. You may want to make friends with your local Allen dealer for that plug that goes into the gyro. I think it's the same as mine. I'll find out.

I took the obsolete plugs on my amps off and replaced them with the more common audio-video BNC twist-lock plugs. But... you're just needing audio, and we can find the connections inside the amp, but let's not worry about that now.

So, do you see two smaller cables that go to the pedal? Those will go to the amplifier. They may have a wire sheath (shielded cables) so they may not be physically smaller.

I think the four wires you found in the cable will go to the gyro. (I like that style of gyro switch. My '59 has it, but they went to stop tabs on my '67. )

Also, do you have a photo of the connections on the back of the big speaker array? It will attach to the terminals that already have wires on them on the amp - the screw terminals.

Jarrett, the presence of the AC power sockets suggests that everything turned on and off with the organ. (One for the amp, one for the gyro.) You don't HAVE to do this, of course.

And now I want to discuss our friend Organkeys Jones saying that the only part of value is the amps. (I'd say it's the keyboards.) However, I have a "67 Allen with a gyro and five other huge speakers, and I wanted to hear what it sounded like in 1967. Thus I went to lengths to update only things that completed a power path, like wires and plugs and connectors and terminal screws and spacers. So I have a 1967 Allen organ that everything works on and I daresay that plays like it played in 1967. I am a hobbyist, and our friend Organkeys Jones is looking at it from an organist's perspective. They expect the thing to work on Sundays. To a hobbyist, this stuff is just fun to mess with (and play). I think it's perfectly valid to get this old organ working for a practice device. Is it the be-all and end-all of organdom? Well, no, but what is?

And furthermore, philosophically Allen deliberately made these old boogers so the stops sound pleasant when mixed together. They don't remotely sound like pipes, but they do sound nice. They sound nice for 100-200 people at a time, which is what MY organ was intended for. I imagine that the 90-watt amp in this organ served a similar crowd, and this organ is going to sound nice, too.

[Silken Path]

Jarrett, if you take a photo of that female socket to your local electronics repair place, they will identify it as some sort of Amphenol connector that they have in a drawer or a bin. You can ask them to make up a "pigtail" for you and later splice it into the control wires.

Also, if you know an old ham radio operator, he may have that plug in HIS parts boxes. They were common on WW II gear, and many hams bought military radio stuff when it became surplus.

I haven't found a good diagram yet for that gyro controller, but I suspect I have it here somewhere.... Found it.

Pin 1 is ground, pin 2 is normal, pin 3 is celeste, pin 4 is 14 VDC. That 14 volts come from the main power supply of the organ. "Normal" means a lazy idle. Celeste is the full-speed. I verified on my organ that it will play with the gyro unplugged. I suspect that the gyro is the only tremolo provided on your organ so you will want it working.

The gyro control is an interesting device. When you move from normal to tremolo, it ramps up the voltage instead of just dumping the high voltage on the electric motor. If you look beneath the controller, you'll see the markings for the different voltages.

Our friend Organkeys Jones is right about the amplifier. Allen has a service bulletin from 1981 saying that they will no longer repair the tube type amps and technicians should use the "modern" transistor amps instead. I found out from myorgan that an inexpensive modern Behringer mixer can be inserted in the audio output lines of the organ, and I tried it on mine. This not only gives us headphones, it also allows modern self-powered speakers to be used. A mixer could also take the place of the amp to be followed by a modern amp AND the old speakers. So don't worry about repairing the amp, if it comes to that.

Let me know if I'm killing you with information... But these ancient Allens used a very different theory about loudspeakers. Instead of having a few very efficient drivers that move a lot of air, it used many, many smaller drivers that moved a little air each. The net effect is that if you stand in front of one of these old speakers, you can physically feel the movement. And my gyro is in a stack of itself, a 16-driver speaker, and a dual bass speaker, all driven by only 50 watts.