Newbie Subwoofer Setup

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Oct 13, 2005
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This is a big duh question. I received my Grotto sub for hook up with my Ascents. According to the owner's manual, I connect the sub to my amp/preamp using both interconnects AND speaker cable. Why? I'm just running two-channel, why do I need to use interconnects to run the sub? Seems one or the other would do the trick.

Thanks for the guidance.
I skimmed the manual on-line to see what you were talking about. I don't see where it says to do both. You are correct that one or the other will do for 2 channel listening. Hook up the line level to your preamp or the speaker level to your amp or speakers (running full range).

For LFE, it has a separate input for the 0.1 channel.
Use the line level from your amp/preamp. This is how I have mine setup. My setup is a bit different but this should be more seemless. Also if you can run the LFE to a surround processor if you have that "kinda stuff too" :D will help with DVD's

Good Luck

Jeff :cool:
Just make sure not to use the LFE input if you don't have a surround processor. The LFE input does NOT make use of crossover circuits in the sub.

As already stated, I would just run a pair of line level RCAs from your preamp. I don't like speaker level, paranoid about having something else in the chain from amp to speakers.

I appreciate everyone's input. Sounds like running a pair of RCA interconnects from my preamp outs is the way too go. Guess I'll need an extra long pair.
output555 said:
I appreciate everyone's input. Sounds like running a pair of RCA interconnects from my preamp outs is the way too go. Guess I'll need an extra long pair.
Hola...yes, and you can make them or you can buy it at Radio Shack as an example. Remember, due to the fact that this cable is only for low frequency, then the lengh will not affect your overall system sound. Most of the preamps have two outputs, use one for your amp. and the other for the sub, if not, with two "Ys" you can solve it also, two females with one male RCA connectors...happy listening,
For an extra long run, you can use RG-6 coax

I have RG-6 running from the preamp outputs, down through the wall, across the basement crawlspace, and into the wall on the other side of the room. A nice clean looking wall plate accepts the coax on the back, and use a pair of short interconnects out the front and into the sub. This allows more flexibility w.r.t. sub placement. The long run of coax will be just fine if you're worried about sound quality.
Why Y?

If my preamp out has a right and a left output and my Grotto has a right and left input, why would I run a Y-connection? Seems most "subwoofer cables" are configured this way. Either that are they are just a single interconnect--as in a mono run? So, again, why would I not run a pair of interconnects: both right and left?
You would run a Y-connection if you only had one set of outputs on your preamp. You'd need one run of ICs to go to the sub and another to your main amp. Not all preamps have dual sets of main outputs.

Most mono runs are for connections from a processor, either for the 0.1 channel or a "combined" L/R signal depending on how the bass management is set up.