Sub-woof wiring with a 5-channel amp? [Archive] - Audio & Video Forums


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12-23-2008, 08:07 AM
:cryin: Alright. Iím going to ask the question. You guys can make fun of me, or even kick me out of the club if you want.

The fundamental thing I want to know is, what is the common method of wiring a sub woofer to a 5-channel amplifier?

The details: My pre-amp is a Rotel RSP 980. It has a sub-out jack. This unit feeds a Carver AV405 5-channel amp. Of course there is no dedicated output for a sub. The sub-out jack on the pre-amp does not have enough gain to drive the sub.

The sub is 60 watt powered P.O.S. (piece of s_ _ t) that Iíll replace in due time. Do I need to get an additional 2-channel amp to drive the sub? Can is be wired in series to the fronts?

Iím sure this seems a ridiculous question for those of you with vast experience. But for old guys like me who grew up in a two-channel world you answer could be useful for more than just me. (Maybe not- but I tell myself that to make me feel better =).

Thanks for the help.

12-23-2008, 08:43 AM
Most subwoofers, yours included, are powered and a standard coaxial cable with RCA connectors on both ends is the norm.

You would run this from the sub-out jack on the RSP 980 pre-amp to one of the line level inputs on the subwoofer. You say your subwoofer is a "60 watt POS". It may be small but hey, it's all you've got for now.

12-23-2008, 09:30 AM
Thanks very much. I can't remember exactly the jacks on the back of the sub, but I'll check it out. Thanks again

N. Abstentia
12-23-2008, 05:41 PM
Well, you can't drive that sub with that would need a passive sub.

Mr Peabody
12-23-2008, 07:55 PM
Mark told you the correct way to hook it up but the truth is the sub has way less power than your Carver amp and it's not going to be able to keep up. It takes more power to reproduce low end and 60 watts is a drop in the bucket compared to 5 channels of how ever large the Carver is. 60 watts would be like for a computer or possibly a HTIB.

The ONLY way this may even work is if you go into the set up menu and turn the front/center/rear volumes practically all the way down while giving the sub volume (still in the set up menu) full volume. Keep the volume on the subwoofer below 11:00 on the dial or you are liable to send it into orbit. The sub amp is only 60 watts and if the preamp internal volume is full up giving the sub max gain you need to keep the sub's volume low enough to give it some head room (allowing a bit of reserve for peaks).

If it was me, I'd unhook the sub, set the internal preamp to "no sub". This will send the bass to your main speakers. This set up will be much much better than trying to have that rinky dink sub work as a sub in conjunction with a large Carver amp.

12-24-2008, 09:36 AM
Thanks Mr Peabody. It sounds like a new sub will need to be upgraded sooner rather than later. My mains are Paradigm Monitor series 9 which should be able to handle that load (better than the sub if understand you correctly).

I appreciate your help (and patience).

Mr Peabody
12-24-2008, 10:41 AM
Better than the sub you have now any way. Using "no sub" for now will at least give you an even response.

When you look for a sub try to find one with more power than your Carver. It's hard to say how much larger because amps vary in quality. Maybe a target could be twice the power. You will have to go into the set up menu and set the volume controls, so you can't go too wrong unless it was too small again. Even if it was the same power rating as the Carver you could tweak the internal volume of your receiver/preamp to make it work, it just becomes difficult when the sub amp is too small to keep up.

Maybe post back once you've tried it without the sub to let us know how it went.