Video Asylum

Posted by David Aiken (A) on January 30, 2011 at 21:55:16

In Reply to: RE: stupid question on sub hookup posted by dpy on January 30, 2011 at 20:49:24

on the receiver and the sub.

First, the sub. I've got a REL with 2 RCA inputs but both are mono, just wired internally for different gain levels. You only connect to one of them so you run a single connection from the receiver's sub output to one of the sub's RCA inputs. Some subs may have "stereo" RCA inputs and sum the signal from both internally, so you would need to run a Y adapter to them and connect that to the single receiver output. You need to look at the sub's manual to find out what to do with the sub.

Now to the receiver.

AV receivers have inputs for a low frequency effects channel, the ".1" channel in 5.1/6.1/7.1 surround sound recordings. The problem is that the sub output doesn't exclusively take the output from the .1 input channel.

AV receivers have sound management options which you access via the receiver's setup menu. What those options allow you to do is to simply feed the LFE channel to the sub, or to feed it low frequency content from other channels below a crossover frequency you set in addition to any .1 channel signal, or to feed both the sub and the speakers the low frequency content from other channels (what is called "double bass" since you're actually doubling up with the sub and speakers for that content) plus any .1 channel input.

These bass management options work with any input, no matter how many channels, so a 2 channel music input can have the sub handling low frequencies from those 2 channels either instead of the speakers or in conjunction with the speakers if you select the "double bass" option, or you could run the speakers alone without the sub.

At the receiver end it all depends on the choices you make in the setup menu and those can vary slightly from receiver to receiver, especially in relation to the terminology they use to describe the options. You probably need to read the manual in order to understand the options his particular receiver has and, in my experience, the way a lot of this stuff is explained in the manuals leaves a lot to be desired.




David Aiken