[Wayner]

I recently bought a REL T-5 subwoofer. It's a small guy (12" cube), with an 8" woofer and a smallish plate amplifier. REL does a little different take on subwoofer connections. Their preferred method is not to use an LFE input, but rather (with supplied cable and Speakon connector, at one end), would rather their customers connect the sub to the speakers outputs (those amps that have common ground) which almost all are today, at least Frank's are.

The input impedance of the T-5 is around 170,000 ohms, so the amp will not even know the sub is connected. What this means is that the mains are connected to the amp as normal, then the cable going to the REL is connected with 3 wires, one for left channel, one for right channel and common at  the amp, and then connects to their sub with the speakon.

Then dial the cross-over way down and let the sub continue where the mains left off. It blends really well.

So I also have an old ARS300 (Acoustic Research with a Carver Sunfire amp plate), and it also  has the more traditional "high level" inputs. I hooked this amp up the same way, running wires to my mains in the regular fashion, and then ran wires for left and right from the amp to the sub. Same kind of results. Seemless integration. I don't know why I didn't see the light before, But now I think all subs should be hooked up this way.

Wayner

[Mark Korda]

Hi Wayner, what is a LFE? Wayne, I have a subwoofer I built from Parts Express stuff. I have a BASH sub plate amp. My main amp is a Dyna ST-35 that's been in your shop before. I love it. I have every thing hooked up with Y cables from my cd player to both amps. I think you know the hook ups for speakers on the stock Dyna amps. I read your hook up method and I'm not catching on. I would like to try it if its possible. My plate amp has volume and cross over controls and provisions to connect the main speakers. Thanks Wayne if you got the time....Mark Korda

[Wayner]

LFE is low frequency effect. It is a line level signal, usually fed from preamps that have a sub output at line level, using an RCA interconnect, more so with multi-channel preamps.

Well, lots of preamps do not have this line level output. Using the speaker input, allows you access to the signal from the power amp's speaker output terminals. You simply runs a couple pairs of additional wires from your amp to the sub amp plate.



Why go thru the sub-woofer's cross-over network to your main speakers? It's kind of pointless and probably does more harm then good. This way, speakers are unaffected by the sub, and the sub simply runs off of the speaker's output signal. Blend in the sub with the bottom end of your main speakers and there you go.



Wayner

[Wayner]

Also note that your sub-woofer and the power amp should be on the same outlet or power strip. I will start another thread on this very topic.

'ner

[dlparker]

Also note that your sub-woofer and the power amp should be on the same outlet or power strip. I will start another thread on this very topic.

'ner

Looking forward to reading the new topic. You may even inspire me to move my eqpt shelves, dig my way through the spaghetti, and reroute and rewire some stuff..

[charmerci]

Why go thru the sub-woofer's cross-over network to your main speakers?

Wayner

Well, generally you'll get a bump or a dip near the frequency response where the speakers and sub roll off.

[mcgsxr]

I understand that letting your mains run full range and then blending a sub underneath works - I have done that with most of my 2 channel setups.

The use of speaker level connections vs line level though I understand less.  I would think the same net effect could be achieved but using L and R RCA connections, and bringing the sub in under the mains.  This is the way I usually do it.

[Phil A]

I use Rels a long time (and mine are older models).  Have four of them (in the old house that was my solution for multi-channel music bass management - now 2 Storm IIIs in the main system, a Strata III in one back-up system and a Q150 in another.  They have both hi and low (line) level inputs.  The hi level inputs have their own volume control and crossover (and connect via a Neutrik 4-Pole Speakon connector).  The use of the hi (speaker) level inputs is supposed (at least the way they used to market it) steal a drop of signal from the amp and therefore in some ways end up mimicking the sonic characteristics of the amp.

[I.Greyhound Fan]

Velodyne use to prefer that you connect their subs at the amp vs line level.

[Tone Depth]

Doesn't using a sub woofer crossover remove the lowest frequencies from the signals that the main speakers reproduce, in theory, and therefore reduce the distortion and increase the efficiency of the main speakers? That seems like basic crossover design.

I do understand that by hooking up the subs in parallel, the main speaker roll off may or may not be audible.

[luke357sig]

Group,
Have some questions.  I currently connect my T8+ to a Rythmik sub.  After reading this I was wondering about switching to connecting my Insight+ Double 440H to the sub.  I have 2 extra sets of speaker cables.  One bare, the other banana.  My current connection to speakers is banana.  Questions.  First, is there some kind of connector that would fit the 440H to handle both my current banana connections plus another set of cables bananas? Or current banana connection plus cables with bare connection?  Second, should I leave things alone and keep my current line level connection?  IE no advantage?  Thanks folks.

[srb]

Edit: DELETED (misread)

[NIGHTFALL1970]

Luke357sig (cool name, I get it!),

The instructions from my Rythmik sub says:

 LINE LEVEL/ HIGH LEVEL INPUTS:
(Subwoofer) amplifier accepts both line level and high level (or speaker level) inputs.  Line level outputs are filtered at 80 Hz.  One should use line level inputs whenever possible,  except where very long interconnects leads to noise problems."

[Tone Depth]

In past research, I vaguely recall seeing stacking banana plugs which could make the connection you are seeking. Maybe check the Pomona website.

Group,
Have some questions.  I currently connect my T8+ to a Rythmik sub.  After reading this I was wondering about switching to connecting my Insight+ Double 440H to the sub.  I have 2 extra sets of speaker cables.  One bare, the other banana.  My current connection to speakers is banana.  Questions.  First, is there some kind of connector that would fit the 440H to handle both my current banana connections plus another set of cables bananas? Or current banana connection plus cables with bare connection?  Second, should I leave things alone and keep my current line level connection?  IE no advantage?  Thanks folks.

[jpm]

Seeking a point of clarification, it would be unwise to run an amp's speaker output direct to a line level incorrect, right?

I use an older JBL Synthesis sub to partner KEF LS-50's and a Devialet 120. The JBL only has a line level input and the Devialet has no dedicated subwoofer output. I use a (startlingly inexpensive) auto-parts-market adapter designed for purpose to provide the resistance. 

The combined results are stunning and the JBL blows away the two REL subs I had before but was never able to get to sound right, despite being designed to be connected the right way

[srb]

Seeking a point of clarification, it would be unwise to run an amp's speaker output direct to a line level incorrect, right?

Worst case scenario, it could spell disaster for both amp and subwoofer.  Best case scenario, maybe just kill one of them! 

[sunnydaze]

Group,
Have some questions.  I currently connect my T8+ to a Rythmik sub.  After reading this I was wondering about switching to connecting my Insight+ Double 440H to the sub.  I have 2 extra sets of speaker cables.  One bare, the other banana.  My current connection to speakers is banana.  Questions.  First, is there some kind of connector that would fit the 440H to handle both my current banana connections plus another set of cables bananas? Or current banana connection plus cables with bare connection?  Second, should I leave things alone and keep my current line level connection?  IE no advantage?  Thanks folks.

I don't know your AVA amp,  but i assume it has 5 way binding posts?   If so,  use a cable to sub that has either bare wire or spade on amp end.   This will fit on AVA post,  along with current banana on cable to speaker.

Whether this connection is superior to line level,  only you can determine.   Try it and see.

[jpm]

Best case scenario, maybe just kill one of them! 

Hopefully nobody has rushed out to try this since the thread started 

[luke357sig]

jpm, I was thinking about connecting my amp to the subs high level input, not line level input. That would have been REAL interesting....

[Wayner]

Hopefully nobody has rushed out to try this since the thread started 

I clearly stated that it must be connected to the sub-woofer speaker inputs, not the line level.

I also supplied a wiring diagram.

Maybe you need to read the whole thread and your sub-woofer's instruction manual.

Nothing can be engineered to prevent stupid.