Help with Allen ADC-2110

[jepsound]

I now have an Allen ADC-2110-T organ which was given to me. This model has no internal speakers. It does have a 4-channel power amp. The previous owner had it connected to 4 speakers. Now, in my space, I only have room for 2 speakers. I know that Allen has dip switches on the preamp board to mix down to 2 channels, but I do not know the proper configuration of these switches and which channels of the 4-channel amp are used in a two-speaker configuration. My preamp board is a USRM-3 while my service manual only shows a USRM-2 diagram. This is my first time working with an Allen digital so I need some friendly help or advice.

Thanks,

Jim

[sraevsky]

I'm going to bump this thread and ask, did you ever receive an answer? I'm getting an ADC-2110 soon with two speakers and hope to make the same change you did.

Thanks

[jepsound]

I'm going to bump this thread and ask, did you ever receive an answer? I'm getting an ADC-2110 soon with two speakers and hope to make the same change you did.

Thanks

Thanks for the question. When you read what I say below, bear in mind my 2110 has a 4-channel audio system so this might not answer all of your questions if your has the 2-channel system.

No, I did not ever get a reply on this issue. Since I did not find out any info on the USRM-3 card, I decided to do the following:

I removed the inputs from the 2110 amplifier and connected them to an external audio mixer capable of handling the 4 inputs. The output of the mixer went to two external amplifiers. (you could reuse the internal Allen amps in this same way). I then mixed those 4 inputs to send most of the flute voices to my external Leslie and the remaining voices to the 2nd external amp and to a good quality speaker with a 15-inch woofer and horn tweeter. Once I had a suitable mix, I added some reverb to add fullness to the sound. My mixer had a digital reverb built in so that was easy to accomplish.

I used this setup for a couple of months and found that the lower pedals were causing distortion in the sound. To cure this, I added a powered JBL subwoofer to both mixer output channels and used the mixer and subwoofer tone controls to direct most of the bass to the subwoofer.

I am very happy with this arrangement. It gives me great flexibility in voicing my instrument. This could also be accomplished with two regular high quality speakers instead in one speaker and a Leslie.

Please ask more questions if needed.

Now that I've said all that, I would still appreciate any info anyone might have on the USRM-3 card per my original post.

Jim

[jbird604]

IIRC, on the USRM-3, the four DIP switches allow blending of certain inputs into a single output. For example, if you move switch 1 to the on position, the inputs on J466 and 467 will be combined and output on J475. Likewise, if you turn on switch 2, inputs J468 and 469 will be combined and output on J477. Turning on switch 3 combines the inputs on J472 and 473 and outputs them on J482. (Switch 4 is not used and has no effect on anything.)

So, if you wanted to easily blend the four channels of your cage output down to two, you could use the above jacks. I believe the card reader outputs get mixed with the swell channels on a USEM-1 board before going to the expression boards.

I believe the USRM-3 is identical to the USRM-2 except that the -3 version has provisions for stereo reverb units.

[sraevsky]

Interesting comments everyone. I am constantly amazed at the depth of knowledge people have about these organs.