Subwoofer connection question (1 Viewer)

[Jon_Are]

From the beginners primer and FAQ, on subwoofer connections:

It is better to connect the receiver's LFE out to both of the subwoofers "L and R" inputs. Essentially, this will provide a volume level in the subwoofer twice as much as just connecting to the "L" alone, or the "R" alone.

Is this true? How would you derive twice as much volume by splitting the signal? Right now, I have the receiver's LFE OUT to just one ("L" or "R") sub inputs.

Thanks,

Jon

 

[Bill Kane]

Jon,

First, your connection is AOK.

This question pops up in regard to using a Y-splitter at the sub end. It’s not normally necessary. Adding the Y-splitter doubles the receiver SubOut voltage into the sub amp. It’s like connecting two elec'l extns out of one 120V wall outlet = two 120V feeds.

It’s said this L&R linelevel feed boosts the sub signal input by 3dB as the sub amp sums this mono signal and passes it along. A 3dB increase at the volume OUTPUT end equals doubling of the sound. This is where the “doubling” reference comes from but it’s inaccurate since we’re still at the INPUT stage.

The reason it isn’t necessary is because when we go to calibrate the sub with our disk test tone, we take that boosted sub output and merely reduce it with the rcvr bass/LFE and sub amp controls back down to our reference level to match the front speakers.

But some people report they dont get enough subout voltage – in combination with their rcvr and sub amp – even with controls turned up. This can show up when the sub amp Auto-On feature doesn’t always wake up. For them, using a Y-splitter often helps as a workaround boost.

bill

 

[Jon_Are]

Thanks for the quick and succinct answer, Bill.

Now I have to get me one of them thar calibration disks; been putting it off for too long.

Jon

 

[Bill Kane]

...sad news losing 7 astronauts this am with NASA shuttle break-up over Texas:frowning:

for the disk, spring $15 for this one at amazon.com

HERE