Disintegrated Woofer Allen

[PghBear210]

Greetings All 😁 I recently purchased an MOS2 with 2 external speakers & found both to have disintegrated foam around the 12" woofers. Can anyone point me toward a reasonably priced resource to replace the raw speakers?? Nothing elaborate is needed as It's filling the cavernous space of my 14' square living room. Cheers to Everyone!

[jbird604]

The best advice is to buy a speaker re-foaming kit and fix the woofer instead of replacing it. It's not brain surgery, but it does require some patience and skill.

If you're not interested in doing that, you can replace it with any decent 12" woofer. That is not one of the more common Allen cabinets, such as the HC-12 or HC-15, but appears to be one of the somewhat rare ones built in the 80's and intended to "supplement" the full-size speaker. I suppose the previous owner of the organ was using these smaller speakers as the only speakers, which ought to be fine in a home setup.

If your organ has internal speakers, it will of course play without any externals. But externals do add a nice dimension to the sound.

Here's a top quality 12" woofer from Newark.com that would work, and doesn't cost a lot. I'd go ahead and replace the other cabinets's woofer too at the same time.

https://www.newark.com/mcm-audio-sel...S%2Fw%2Fsearch


Search for part # 55-1255

[myorgan]

John,

I have a better photo of that speaker here: https://organforum.com/gallery/displ...um=36&pid=1238.

PghBear210, when you remove the woofer, make sure you keep track of the polarity. When you replace the woofer, you will need to keep the same polarity. If you don't connect it properly, the bass speakers could cancel each other.

Michael

P.S. Do you have the model number of the MOS-2 you purchased?

[PghBear210]

AC-7967 is the model. I've been rebuilding it since I had to disassemble the console to fit it up the stairwell to my apartment.
Anyone have a manual??? If you like I can send a photo of the rack as well.. I think there's some wiring from the console going to the external rack that I'm missing as well... I don't believe it was given to me when the organ was delivered. :-(

[jbird604]

AC-7967 would be the serial number. MOS organs don't have a "model" number as such. The metal plate will have a "System" number, such as "System 305" or "System 505-B" or something like that. Since your serial number begins with "AC" you must have one of the "American Contemporary" consoles -- also known as the "spaceship." That's the only Allen console I know of that can actually be dismantled into upper and lower parts, though it wasn't actually intended to ever be dismantled after it left the factory.

There isn't a specific wiring diagram for any MOS organ, but if you have particular portions of the wiring you can't put back together properly, post about it here and I'll see if I can help you figure it out. Also, the service manual you would need to cover a MOS-2 model would be the original MOS manual (for the basics) plus the MOS-2 supplement. Allen charged dealers big bucks for these manuals, though they later issued smaller sets at low cost for specific models. Normally a complete manual isn't needed, and of course Allen doesn't offer these to the general public. Feel free to ask questions and I or someone else here can refer to a manual to help you.

[David Anderson]

I second the refoaming suggestion. All speakers with foam edges will eventually experience foam rot. It's a tedious task, but not that hard.

[John Vanderlee]

That could be done in a half hour. I hate tossing speakers! ;-)

[PghBear210]

Agreed.. The expense is a killer for decent sound. I plan on placing the externals up high directly facing me across the room with the reverb cranked. Nothing loud.. I just want rich sound in the small space.I'm going to voice the entire organ quiet as to not disturb the landlord below too much. :-)

[PghBear210]

I found the re-foaming kit online.. Will order on payday and post an update when I complete the rebuilds. :-) Thanks for the directions. :-)

[John Vanderlee]

Great, let us know! It's money saving skill.

[myorgan]

PghBear210,

What model MOS-2 organ do you have? I know several here find Parts Express to be a good company, with which to do business.

Michael

[myorgan]

PghBear210,

I saw the serial number plate in another one of your posts. The model number of your organ is 125-RTC. I believe you listed the finish number, which is painted, written, embossed, and posted all over the organ.

Hope this helps.

Michael

[jbird604]

Ok, that clarifies it. This is a 125-RTC, which is the self-contained (speakers in console) MOS-2 model with DM capture action. Since it's MOS-2, it has many features that were optional in MOS-1 organs, such as "frequency separation" (the flute and main channel stops are slightly de-tuned to produce a rich ensemble effect), the card reader, and certain other enhancements that are not as obvious. A very nice model indeed!

Since there are speakers in the console, that explains why the external cabinets are not HC-12s, as they would normally be for a larger MOS-2 model. Those may be called HC-8, if memory serves. Anyway, they are perfectly good for adding some tonal dimension to a self-contained organ, though not essential of course.

Your idea of placing them across the room and using plentiful reverb should be very effective and make the organ sound much more interesting.

[myorgan]

John,

There is a photo of an HC-8 here: https://organforum.com/gallery/displ...um=36&pid=1238

That is the speaker he has.

Michael

[PghBear210]

Yep. That's the one. :-) Rebuild kit ordered. :-)

[PghBear210]

Oops.
I forgot about this post.

Here are the re-foamed speakers.
They actually sound better than the internal speakers.
Even the channel separation echos slightly off the walls between the console and these speakers.
Good choice to rebuild.

BLB2k

[jbird604]

I was going to remark that this is the perfect setup for a "closet organist," but maybe I shouldn't.

Nice repair job though! Allen HC cabinets can't be beat for good solid organ sound, and yes, they are quite superior to the internal speakers in most Allen consoles.