SVS Hook Up

Early B.

A friend of mine just purchased an SVS 25-31 passive sub. He has high-end separates for his two channel stereo system and a home theater system powered by a Denon 1082. He asked me if I knew the best way to hook up the sub both to the stereo system and to the home theater system. I told him I wasn't sure, but I'd ask the Polk folks.

Thanks.

Dr. Spec

It really depends on the amp he will be using to power it, and also on the features on the two channel pre/pro.

The 1082 has a subwoofer pre-out and all the bass management should be done at the 1082 for HT. Just connect the sub pre-out to an appropriate input on the external amp and you are all set there.

For two channel, does the pre/pro have any bass management features at all? You will need a hi/low pass filter network somewhere in the loop to send the appropriate signal to the external sub amp, much in the same way he will be doing with the 1082.

Early B.

Dr. Spec --

No, he doesn't have bass management features on his pre amp.

Can you elaborate on the "high/low pass filter network" that he'll need. I'm not familiar with it. Is it some sort of additional device he needs to buy? If so, is it something he can pick up at Radio Shack?

What sound can he expect from the sub and his stereo speakers if he does not use a filter network?

Dr. Spec

If he doesn't have BM capability in the pre/pro, I strongly advise a subwoofer type plate amp with high level speaker inputs and a filter. He will connect the speaker amp outputs to the sub plate amp and set the plate amp filter to whatever crossover he needs, and then go from the sub plate amp out out to his mains speakers.

He can still send the 1082 sub pre-out to the low level connection on the sub plate amp.

What he really should have bought was a powered 25-31PCi which has a high quality 325 watt BASH plate amp in place which has all the hi/low level connections and filter in place. When he watches movies, he disables the SVS filter. When he listens to music, he enables it for the high level connection. Piece of cake. He can leave all of them connected at the same time.

If he is under the 45 day return window, he should get the powered model and make life easy on himself.

RuSsMaN

What speakers does your friend own? He might not need any friggin 'bass mgmt' at all.

Does anyone ever just throw a passive choke an SVS?

God I hate plate amps, everyone isolates their entire system SHORT of the amp that powers the sub. Let's put it RIGHT on the box - no vibrations there.

Dr. Spec

He definitely needs BM for HT, and the 1082 can do it. In that case any external amp can be used to power the passive SVS.

For his music rig, it's another story. If his pre/pro can't do it, something else needs to have a filter network and the plate amp sprung to mind and have all necessary connections in one spot for both HT and music.

He did ask about how to use the SVS for both applications, so I never considered whether his mains might be adequate without the SVS. It just wasn't part of his original question.

If he wants to use a true external amp, then he'll needs an external xo for the pre/pro for music - simple enough to acquire. Depending on the design of the mains (sealed or vented) he can even specify the rate on the high/low pass filters in the xo to best match the characteristics of the mains. A vented design on the mains could use 24 dB/octave high pass, whereas a sealed design might work better with a 12 dB/octave high pass. The low pass filter could then be selected accordingly for the SVS to make a nice transition with minimal overlap.

Early B.

My friend has Bohlender Graebner Radia X3 mains -- a planar hybrid. They don't produce enough bass, so he wants to enhance his system with a sub.