Using vintage amp with subwoofer

[ifsixwasnin9]

I have a Sansui AU-517 with two sets of speaker output jacks, no subwoofer output jack. Can I still hook a sub up to this amp? Can I use the sub (with low-pass filter) in the second speaker position and my full-range speakers (with high-pass filters) in first speaker position? (Assuming that impedances are matched, of course. I'm not sure if the speaker connection can be bridged for a subwoofer 4-ohm though.)

 

[markw]

Unless your amp has preamp outputs, make sure that whatever powered subwoofer has right and left speaker level inputs. These generally have speaker-level outputs as well and they are generally high-passed at some preset frequency. Connect your mains to these to avail yourself of that option.

Don't even think about "bridging". It ain't quite as simple as you (and many, many others) think it is.

 

[ifsixwasnin9]

If I use a powered sub it can be connected to any full range speaker? And where is the best place to connect the sub? My amp has pre-amp outputs.

 

[markw]

If I use a powered sub it can be connected to any full range speaker?

Yes.

And where is the best place to connect the sub? My amp has pre-amp outputs.

If your amp has power-amp inputs as well as preamp outputs, you can connect the sub there, in-line between the pre and power amp.

Depending on the sub you select, you may be able to implement a rudimentary "high-pass" filter for your mains with the sub's internal crossover/sub amp. This is generally available at speaker-level outs but line-level outs may act differently.

Read the sub's manual carefully before purchasing.