I have a Mirage Omni S10 sub I want to connect to a Cambridge Audio 840A integrated amplifier. The amplifier has 2 RCA preamp outs (left and right) and the sub has only 1 RCA mono input.

How do I make this connection possible? Do I use only one of the channels on the amplifier? Is there any way to combine the 2 channels on the amplifier in only one coax cable without running the amplifier mono?

A RCA splitter from Monoprice.com would do the trick... However...

Your integrated doesn't specifically seem to support subwoofers specifically. You can send it to a sub, but there would be no limit to what it is sending there (e.g., on a receiver built to do this you can tell it stop sending signals to the mains, and only to the subwoofer pre-out at 80Hz, or whatever you choose). Still, to try it, flip the "Filter" switch, and set the frequency control to some point (low mixed or below your mains). Play with the volume setting, etc.

Good luck!

A RCA splitter from Monoprice.com would do the trick... However...

Your integrated doesn't specifically seem to support subwoofers specifically. You can send it to a sub, but there would be no limit to what it is sending there (e.g., on a receiver built to do this you can tell it stop sending signals to the mains, and only to the subwoofer pre-out at 80Hz, or whatever you choose). Still, to try it, flip the "Filter" switch, and set the frequency control to some point (low mixed or below your mains). Play with the volume setting, etc.

Good luck!
Thank you hifibitn for your reply!
As a matter of fact the CA 840A manual shows connection to sub from preamp output to sub inputs (left to left and right to right); but my sub has only 1 input (mono LFE).
So you think that putting a RCA splitter on the preamp outputs wouldn't be a problem?
I was concerned that by doing that I would trigger the amp's circuit protection (see the splitter as a short between the 2 channels)

A RCA splitter from Monoprice.com would do the trick... Nope. It will likely shunt together the L and R channels for the main amps/speakers unless it is buffered. You can try it and see if it causes the loss of all separation.

Otherwise, I suggest that you run it from speaker wires connected to the main outputs of your amp in parallel with the main speakers.

It will likely shunt together the L and R channels for the main amps/speakers unless it is buffered. You can try it and see if it causes the loss of all separation.

Otherwise, I suggest that you run it from speaker wires connected to the main outputs of your amp in parallel with the main speakers.

I defer to you certainly, but wouldnt running a splitter in reverse create a joiner? The point here is to go from 2 to 1, no? SubWoofer being mono, does it care about separation? The OP says his manual shows this type of arrangement (though I gather that it is going from L/R Pre-Out to L/R In on the sub in the picture). I didn't see that in the manual I downloaded...

I preface all of the above with "I have not tried this at home" ;)

It will likely shunt together the L and R channels for the main amps/speakers unless it is buffered. You can try it and see if it causes the loss of all separation.

Otherwise, I suggest that you run it from speaker wires connected to the main outputs of your amp in parallel with the main speakers.
Thank you for your reply Kal!
What I think you're suggesting is to connect my 2 speakers to A (main speakers) terminals on the amplifier and to connect my sub High-Level terminals to B (secondary speakers) terminals on the amplifier and to set the A/B speaker switch on the front of receiver to A and B.
Is my understanding correct?

I defer to you certainly, but wouldnt running a splitter in reverse create a joiner? The point here is to go from 2 to 1, no? SubWoofer being mono, does it care about separation? The OP says his manual shows this type of arrangement (though I gather that it is going from L/R Pre-Out to L/R In on the sub in the picture). I didn't see that in the manual I downloaded...

I preface all of the above with "I have not tried this at home" ;)
This is what my CA840A shows for sub connection:

This is what my CA840A shows for sub connection:And that will work just fine provided you have R/L inputs on the sub. But merging the R/L outs with a splitter will in all likelihood create a problem.

I defer to you certainly, but wouldnt running a splitter in reverse create a joiner? The point here is to go from 2 to 1, no? For the sub, yes. However, if the preamp outputs are connected, internally, directly to the signal lines going to the integrated's power amps, adding this 'combiner' will connect them together to make mono.

I preface all of the above with "I have not tried this at home" ;)Nor have I but I do know that it has been an issue with some amps.

Thank you for your reply Kal!
What I think you're suggesting is to connect my 2 speakers to A (main speakers) terminals on the amplifier and to connect my sub High-Level terminals to B (secondary speakers) terminals on the amplifier and to set the A/B speaker switch on the front of receiver to A and B.
Is my understanding correct?That's fine. I didn't know your amp had A/B terminals.

So I've got the same situation. I've got a Mirage Prestige S8 coming tomorrow that has only one RCA input. My 10 year old Harman/Kardon AVR 20II has an RCA left and an RCA right that the owner's manual says:

SUBWOOFER OUT:
When a seperate power amplifier is used to drive a subwoofer connect the power amplifier inputs to the jacks.

Should I just use a Y-cable or would this create internal shorting? It seems nobody has really committed to a direct answer yet. I've got a tSc ASW-10 hooked up now with left and right RCA outs going to RCA left and right ins and it is working this way.


OK so you've individually committed to answers but they don't seem to be the same one!

Should I just use a Y-cable or would this create internal shorting? It seems nobody has really committed to a direct answer yet.That's because none of us has those pieces of equipment and, therefore, we cannot know for sure, have not tried it. The manufacturer never deals with the issue in the manual. All I can say is to try it. If it works, fine. If it shorts the two channels and makes everything mono, you are only out the cost of the adapter.

Hey, here's an even cheaper, faster test. While playing a stereo program, run a plain RCA-RCA interconnect from the L preamp output to the R preamp output. If the sound is still stereo, buy the Y-adapter. If the sound goes mono, unplug it and use the speaker connections.

There's also a DIY solution but I hesitate to suggest that.:eek:

For the sub, yes. However, if the preamp outputs are connected, internally, directly to the signal lines going to the integrated's power amps, adding this 'combiner' will connect them together to make mono.When he says make mono, he doesn't mean it makes a mono signal for the subwoofer (which it does). He means that it will make the output of the amps to the speakers mono. And likely do some other weird things. Like bypass the volume control.

Like bypass the volume control.It won't do that. If it could, I would not suggest trying it.

It won't do that. If it could, I would not suggest trying it.OK. I thought I remembered someone complaining that, besides creating a mono signal, that had also happened when they merged the R/L outputs. Or something weird like that, anyway.