How to add a Subwoofer to 2 channel stereo setup?


I hope this doesn't sound stupid, but I am looking to add a subwoofer to my system, but am somewhat unsure about how to do so. I have both a stereo preamp(Classe CP-50) and amplifier(actually a couple of stereo/mono amps- Monarchy Audio SM-70 Pros) which I use to drive my front speakers. However, as they are small bookshelf speakers, they have rather limited frequency response only going down to about 70 Hz or so. I am looking to add a subwoofer to extend the bass response, but don't know how to connect my sub. To what output?

I have tried outputting the signal through a line-level sub/LFE interconnect directly from my DVD player's Digital Coaxial out, and the 5.1 channel analog audio output to my subwoofer's(Sony SW-M 500 or something like that) line-level input while of course outputting the front speakers from the Left and Right channel outputs to my preamp, but this doesn't seem to work as there is no sound coming from my sub although the front speakers apparently sound fine. My preamp being only stereo does not have an "extra" line-level input/output for a subwoofer, so I don't know what to do.

I don't know if it means anything, but I believe I have an "active" powered subwoofer, as I must plug in a separate AC cord into the wall. It also has a volume control, frequency response, phase control and everything.

I am hoping to upgrade my speakers to a more full-range model to match my recent amplifier upgrades(in both sound quality and frequency range), but until then is there anything I can do to add my sub?

Also, does anybody have any good speaker recommendations to go with my above mentioned equipment?

I am seriously considering Totem Arros, but they only reach about 40 Hz according to Totem's specs. I have given thought to some others, but given both aesthetic, space and budget constraints(maybe $ 1K for a pair of speakers used), it has been a difficult search.

Anyway guys, thanks for your help, and take it easy.

Thanks,
The Audio Novice in training ;-)
audio_obsessed_novic

Showing 2 responses by wolf_garcia

Wrongo bongo...I use a single channel summing REL and there is no phase cancellation at all. None. Zero. Also, I listen to modern recordings all the time (especially acoustic jazz trios lately) and the bass is usually NOT dead center...often it's panned by the engineer more to the left or right of center although it varies (and the lowest notes are not directional but may seem so from aural cues from overtones). Brad Mehldau's stuff is a good example...bass middle to one side, drums middle to the other, piano across the middle.
One sub (the larger one) is placed behind the left main, and the other against a side wall only because I stick it in a window above it sometimes for outdoor deck enjoyment. Same signal to both (summing the signal, not stereo). When I was using the one (left side) sub you really could not tell where it was particularly, and since bass hugs flat surfaces it was all over the room although it was specifically tweaked for my middle "sweet spot." Since I have the subs set at where my mains naturally start losing their low end ability (mid 50s maybe) they blend well and imaging is unaffected. REL recommends trying the sub in various spots (manuals are easy to find online)…corners, etc., until it feels right, and I agree…you can put a sub over in the corner and it can sound great!