Best Subwoofer Connection for Music


I have struggled to integrate subwoofers into my two channel systems in a way that enhances the system’s musicality. The best system so far is an old, cheap, dual coil subwoofer, but it has limited capability. I have two subs I want to add, one each, to each of my current systems. (Profile still under construction, which I’ll detail below.) I’ve heard PS Audio’s recommendation of the use of high level connections for music (versus low level connection for Home Theater LFE [Low Frequency Effects]), and I caught a comment on one audio YouTube post to be sure your subwoofer had both hi-level IN and Hi-Level OUT. This, to me, means that the subwoofer connection for music being recommended is Amp [Left & Right] —> Subwoofer Input [Left + Right] —> Subwoofer Output [Left & Right, again] —> Main Speakers [Left & Right]. Is this right? Just like the old dual coil subwoofer, but this time, the Subwoofer plate amp is adding Left + Right.

One Sub has both low level and high level inputs [an 90’s RCA 10” 100 Watt unit marketed by RadioShack. The other Sub, 15” 250 Watt from Dayton Audio, has three different options for audio I/O, to include two sets of low level I/O: (1) RCA and Speak-On connectors for low level input, and (2) RCA and XLRs for low level output. Meanwhile, it also has (3) high level spring clip speaker connectors for both input and output.

(1) I would like to integrate the smaller sub into my tube setup which consists of a Rogue Audio RP-9 + Rogue Audio ST-100 Dark 100 wpc feeding a full-range vintage acoustic suspension Warfedale W70E 3-Way which features a wonderful 15” driver, that I sometimes wish had a bit more ‘punch. (2) I would like to integrate the larger sub into my solid state system which features a McIntosh C100 preamp [I’m still learing how to parse McIntosh model numbers] which allows one to connect to three separate amps [Main (unswitched) + Speaker 1 & Speaker 2 (switched)] currently feeding dual McIntosh MC252 power amps bridged to mono, powering 90’s era full range B&W 801M Series 2 speakers with front ports and upgraded crossovers. The B&W speakers could benefit, I feel, from the ‘wrap around’ room-filling bass sound a 15” driver can provide.

The Dayton plate amp is the most recent addition, and if I need to upgrade the plate amp in the old RCA sub, I’m open to that, maybe by Christmas. [I had forgotten it had only ‘one-way’ connections.]

I’m mostly concerned with what connections would allow me most effectively integrate each sub into my two ‘music only’ systems. Thanks for any help you can offer.

128x128oldrooney

@ditusa Thank you, Mike. That was a good read. Thank you, too, for introducing me to a very approachable audiophile expert.
I happen to have an active crossover [Pioneer D23] I can put to good use implementing some of Barry’s connection/integration recommendations.

@czarivey Both of my preamps have separate “processor loops” that I use for integrating EQ. The thing about the tape loops is that the output is fixed at full volume, but that can be an advantage if you’re willing to adjust the sub’s volume independently, I suppose. Also, I’m not sure that, depending on the amp, the tape loops are always identical to line in/out voltage & impedance, but I could be mistaken.

Edit: @czarivey Perhaps I should ask why you prefer to use tape loop. Others frown on it, and I’m curious, not knowledgeable (although I frequently pretend to be so). 

It sounds like you could connect both subwoofers using the speaker-level inputs.  I prefer to not use the speaker-level outputs on the subs to feed the mains running through the subwoofer amp, relying on the subs internal crossover.  I prefer to just connect the mains and the subwoofers speaker-level inputs to the main amplifier speaker terminals.  Then, I adjust the phase, crossover and volume controls on the sub to blend with my main speakers.

Oh, BTW, you can't use tape in/tape out for the sub because it is before the volume control. You can put an EQ in there, but not a high pass filter.

@czarivey I’m sorry, I completely misread your post to mean that you preferred to use the tape loop for your sub. 
 

@paradisecom When I’ve used speaker level inputs on the subs, I’ve connected them as you describe. However, I found the dual coil sub arrangement with included satellite speakers, had wonderful integration, I just didn’t like the sound itself of the compressed satellites or the 8” floor-oriented sub. 
 

@erik_squires It is possible to use the tape loop for a sub, but as you state, you need a way to attenuate the volume; some crossovers have that feature built in, see Mike’s reference above in the first response to my post.