Subwoofer inputs [Archive] - Audio & Video Forums


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12-21-2006, 07:49 PM
What are the differences in the Line inputs and the speaker inputs on my subs?I notice on the subs on my towers the subs operate no matter if the line jack is plugged in or not with the speaker inputs connected,same with the seperate sub I own,is there some kind of control issue with these inputs?I guess my real question here would be if I only have one sub out on my reciever,do I use the speaker levels on my towers amps and the sub out on my sub?

Dusty Chalk
12-21-2006, 09:12 PM
It's an either/or proposition. The speaker level inputs basically convert it to line level before amplifying them for the woofer driver -- you really aren't using your speaker amplifier to drive the subwoofer, it's just using that to get the signal. You can certainly use it in the scenario you describe. In fact, the line level is preferable in almost all scenarios.

12-22-2006, 01:15 AM
Thanks Dusty,I have line outs on my towers,would going out from one of them to my sub work as well?What your saying is as long as that sub gets a signal,right?

12-22-2006, 04:47 AM
The line-outs might work. Are they sub line outs or hi-pass line outs though? A lot of sub amps just pass the signal after the crossover. If that's the case, they're no good to you here.

I would suggest using a Y-splitter. After your receiver - you can then run the LFE line level to your two speakers' subs or add yet another splitter to do all 3 subs. My cousin did just that with his powered towers and subwoofer off a Sony receiver no less!!!
Don't worry about the 2 levels of splitting. The voltage required is extremely low and the receiver is more than up to the task. Any reciever worth its salt will handle this no problem.

Here's a question though - if your speaker's subs operate off the speaker level, why not just run the LFE to the lone sub and let the speakers take care of themselves?
The only difference between the LFE and speaker level that's worth considering is the crossover.
A full range signal needs to be fed to your speakers so the bass can be filtered by the built in sub's crossover. These crossovers usually aren't that steep and therefore not as great for integrating with other speakers/subs. I'll assume the designer has the subs well integrated with the rest of the speaker, but how it will jive with a 3rd sub and 3 other speakers in a 5.1 remains to be seen.
When you run the LFE out from your receiver, you can use the receiver's crossover (usually steeper, and better) and get a much better blend between all your speakers and the sub. This has become the preferred method for providing a signal to a subwoofer.
But maybe with some tinkering around you can get pleasing results either way.

12-22-2006, 08:07 AM
Thanks kexodusc,that clears alot up and gives me more options.

Dusty Chalk
12-22-2006, 08:40 AM
The line outs might be too loud, if they're not controlled by the volume of the receiver.

12-22-2006, 01:39 PM
Dusty you are a mind reader,my Elite reciever has setup on all the speakers,in the manual it states that these controls must be adjusted on screen,I'm assuming the TV.Do I run an RCA from the reciever video out to the TV for adjusting these levels?

12-22-2006, 01:47 PM
ugh, yeah, a rca cable out from the monitor out to a free input on your tv. It's unusual a receiver wouldn't have an OSD that shows the speaker level settings on it's front face though.

The level of the line outs should be a non issue with any actively amplified sub I've ever heard produced. If it's louder, turn down the sub amps volume to match or adjust the receiver setting. Done.

12-22-2006, 02:54 PM
Thanks Dusc,I have read the manual for the Elite 07TX and it says the settings will be on screen of TV,there sure isn't any display showing on the reciever itself when in setup mode,the directional arrows are lit up,for selection though.