Connecting a subwoofer

[dannyg44]

I have a Carver MXR 130 receiver. It has speaker A or B. It also has a selection for both A & B with no sub out. How can I connect a powered sub to my receiver?

 

[scuzzycard]

I would connect the source to the subwoffer. The subwoffer should have line-level outputs that could then go to your receiver, which would then power your speakers.

 

[jsmithepa]

OK, looks like this Carver is from pre-Sub era.

The primary piece you need is a CROSSOVER. This is a circuit (box?) that splits your stereo signal so the correct frequency is sent to the Sub, and the rest to your L+R.

Some subs have this built-in, and you know this because on the back of the sub you will see:

L+R RCA line level inputs (wire your receiver's output here)
Speakers output for L+R (wire your L+R speakers here)

This would also be an active (self-powered) sub and it also powers your L+R, taking away that job from your receiver.

 

[americanaudiophile]

Assuming your sub doesn't have speaker level inputs you can use one of these
http/www.crutchfield.com/p_142LOC80/Scosche-LOC80.html
connected to either the A or B speaker terminal. If you connect it to B you can turn it off for listening without the sub.
Your main speakers stay connected to the A terminals regardless. This arrangement doesn't take any bass away from the main speakers. It adds the sub bass to the bass they already have. You will need to adjust the frequency range that the sub covers to not overlap too much with the main speakers. Then you balance the volume of the sub and main speakers. Any tone or loudness controls on the receiver should be flat or off;