Adding a sub to my vintage setup... help.

[Seaneman]

OK, my current rig is thus:

-VPI Scout> Harman-Kardon 730 TwinPower> a/d/s L7e speakers.

Space is limited and volume level is low-moderate. (I'm just retired from a 30 year career as a live/studio drummer, so I'm good on 'loud' for ten lifetimes.) I love, LOVE the sound of the L7e's, but they don't do much in the booty frequencies... I've been eyeing larger speakers, but don't have room for towers... so now I'm thinking I'll try adding a sub.
Things to keep in mind:
- the 730 only has speaker A/B outputs
-If the sub situation is going to exceed 300-400$, I'll probably keep saving for a better 2 channel solution.
-the L7's are 4ohm speakers, and the 730 manual says it can only drive one set of monitors at 4ohms (shouldn't be an issue with an active sub, but just covering the basses)
-I'm not against tracking down something like the Paradigm X-30 box if necessary
-would like to control the crossover points as much as possible
-I am average intelligence and need a fairly dummy proof wiring explanation.

Any suggestions, solutions, recommendations from you opinionated experts would be Mucho Appreciato.

Sean

 

[hnash53]

Since a powered sub won't suck much if any of your 730 power, you are OK with a powered sub.

Many powered subs have connections for your speakers, so you'll run your L7 speaker wires from the 730 to the sub IN, then run the wires back from the sub OUT to your L7 speakers. This way, the sub pulls the bass frequencies out and sends the rest to the L7 speakers.

Most powered subs have a crossover setting which you set to "hand over" the bass frequencies to the sub. Many people say to set it at about 60-80 Hz but you can fool around with that. Plus most powered subs have a volume knob to set just how much boom you want.

I have a Polk PSW505 sub which is a 12 inch sub. It has one of the smaller footprints for 12 inch subs, and I found that it really enhanced my system. You can easily find these within your price range.

Best wishes.

 

[JoeESP9]

Give a look at Hsu Research.
http://www.hsuresearch.com/products/vtf-1mk3.html

 

[luvvinvinyl]

I used an NHT 10" powered subwoofer to good effect. It had the stand-alone SA-1 amp, that let me integrate the sub into the system, seamlessly. Crossover and gain were adjustable, and accessible, since it sat in the audio rack, instead of being buried in the corner, on the back of the sub cabinet. Very musical and responsive.

 

[drumbum]

Since a powered sub won't suck much if any of your 730 power, you are OK with a powered sub.

Many powered subs have connections for your speakers, so you'll run your L7 speaker wires from the 730 to the sub IN, then run the wires back from the sub OUT to your L7 speakers. This way, the sub pulls the bass frequencies out and sends the rest to the L7 speakers.

Most powered subs have a crossover setting which you set to "hand over" the bass frequencies to the sub. Many people say to set it at about 60-80 Hz but you can fool around with that. Plus most powered subs have a volume knob to set just how much boom you want.

I have a Polk PSW505 sub which is a 12 inch sub. It has one of the smaller footprints for 12 inch subs, and I found that it really enhanced my system. You can easily find these within your price range.

Best wishes.

I don't think this entirely correct. Normally only passive subs have an actual crossover that keeps the lows out the mains. Most active subs are intended for use with a receiver/integrated or pre that has internal crossover settings. The crossover knob on most active subs just limits how high the sub is allowed to play, so as to not double with the mains.

Does anyone know of an active subwoofer that has a true variable crossover?

 

[Seaneman]

I don't think this entirely correct. Normally only passive subs have an actual crossover that keeps the lows out the mains. Most active subs are intended for use with a receiver/integrated or pre that has internal crossover settings. The crossover knob on most active subs just limits how high the sub is allowed to play, so as to not double with the mains.

Does anyone know of an active subwoofer that has a true variable crossover?

As I'm looking around, I see that a few subs have not only a crossover for the sub itself, but some have a Hi-pass filter that sends on to the satellites. In that case they have a low-pass and a high-pass. Seems to be a pretty rare option, and not on anything in my price range, but would be nice to mess with. More like a typical pro-audio PA setup.

 

[Seaneman]

I'm going to look at a Paradigm PS-12000 today for a decent price. It has a pretty good reputation and a crossover. I'm squared away with the options for hooking it up, but now I have a question... It splitting the signal at the Pre-Amp better/different than splitting the signal at the speakers? Since this sub will not have a Hi-Pass filter on the sends, I don't think the mains will gain any benefit from the crossover, as we've been discussing. Therefore, is there an advantage to not splitting the signal from the pre-amp before sending to the receiver's amp section? I believe you lose about 3db with every split, and if that's true, it would have a noticeable effect on the gain structure of the amps. Anyone know if I'm overthinking that? with my setup, the difference would probably be negligible, but my philosophy about this stuff is to avoid compromise on things I can control with no monetary investments. thanks all...

 

[sqlsavior]

I'm going to look at a Paradigm PS-12000 today for a decent price. It has a pretty good reputation and a crossover. I'm squared away with the options for hooking it up, but now I have a question... It splitting the signal at the Pre-Amp better/different than splitting the signal at the speakers? Since this sub will not have a Hi-Pass filter on the sends, I don't think the mains will gain any benefit from the crossover, as we've been discussing. Therefore, is there an advantage to not splitting the signal from the pre-amp before sending to the receiver's amp section? I believe you lose about 3db with every split, and if that's true, it would have a noticeable effect on the gain structure of the amps. Anyone know if I'm overthinking that? with my setup, the difference would probably be negligible, but my philosophy about this stuff is to avoid compromise on things I can control with no monetary investments. thanks all...

Both approaches have their advocates. For adding a typical active sub to a stereo system, I like speaker connections more than line-level, because I believe they help with blending. I let the mains run full-range, with the sub's low-pass filter set at the main's -3 dB down point, as a starting point.

Others believe in relieving the mains of bass duty. That is easier with AV systems. Your concern about signal splitting at line level probably is overthinking it with most active preamp circuitry.

 

[Seaneman]

Well, the Paradigm is in the house... Works like a champ, but is bigger than I'd hoped for. I went with the speaker connections, because I remembered I had a pretty good Niles speaker control splitter in the garage I picked up at the thrift store last year. That arrangement makes for a much 'neater' assembly, I didn't love the tangle of wire in back of the receiver with the splitters in place, and with the Niles box I can audition the setup with/without sub with an easy push of a button. Now to listen and adjust. So far a subtle amount of the sub adds a nice support without getting mushy, but I think it's got some room for improvement. Huge difference with records with modern mastering vs vintage stuff. I guess I'll be fiddling a lot. Thanks everyone for your advice.