Adding Antiphonal Speakers

[jjcricket1958]

Hi All!

I’d like to add two speakers as an antiphonal for the choir on an MDS 25. I’m not really comfortable in just hooking up stuff and hoping it works.

A picture of the relay is attached. You can see that this organ was configured as a two channel setup. I see the connections for an antiphonal relay and a main relay.

Can anyone tell me what to hook where?

THanks

Jim

[toodles]

If you want to control the main and antiphonal speakers using the tabs on the organ, you'll need to get two antiphonal relays. It's probably the UNIVREL (Universal Relay) module, though you might confirm that with your dealer--Jbird, who posts here frequently, probably can confirm that module, too.

The connections for the relays shown in your photo are for driving the antiphonal relay module coils. Typically, the relays that Allen used are low current coils, so their main/antiphonal relay drive circuits won't handle much current--about 35 mA, if I remember right. The tabs on the organ control the relays and the relays control the audio switching.

I'm guessing you want control over which speakers work from the front of the console.

[jjcricket1958]

Thanks for the reply. Yes, I want to control the speakers ( both main and antiphonal) from the console.

[jbird604]

What you see in the pic is the terminal strip "prepared" for installation of an antiphonal relay. Yes, you need to get one of the "Univerel" units from an Allen dealer (or possibly by keeping an eye on ebay, as people sometimes offer them there pretty cheap). They cost quite a bit of money brand new, since this is a specialty product, hand-assembled at the Allen factory, not a mass-produced item.

If your MDS-25 is a two-channel organ (as I think it is), you only need one Univerel assembly. A single Univerel is capable of handling both main and antiphonal switching for two channels. If I'm wrong and yours is a 4-channel organ, you need one Univerel for the Swell division and another one for the great/pedal. But I really think the MDS-25 is just two channels unless specifically modified at the time of order.

The instructions for installing this device are available in the service manuals and the on-line tech site. Once you get a Univerel in hand, let me know and I'll send you a copy of the instructions. It's not rocket science, but it does require a certain amount of general knowledge of wiring, and how an Allen organ works.

[jjcricket1958]

Thanks John. I will keep my eyes open for a Univerel unit.

[John Vanderlee]

I know the type of Univerel that’s used on the later Allens, but any reason the older ones with open frame relay would not work? Like what is used on MOS types?

[toodles]

Note that the spelling is "Univrel", and not "Univerel"--it's a contraction of Universal Relay. I point that only because you might do a word search for the item and a misspelling won't get you the results you want.

No, the older antiphonal relays won't work because their relay coils draw too much current. The correct relay assembly is part number 904-5659.

[jbird604]

Oops, I keep forgetting about that spelling! These units are a bit hard to find, but they have been in use by Allen for decades, so they do show up on ebay now and then.

[John Vanderlee]

Somehow that extra "e" sneaked in there...