I want to use a JL Audio XD400/4 amplifier to drive my front stage two-way component set. This amplifier is four channel but is bridgeable. I have a two channel input signal for the XD400/4. If I read the manual correctly, I need a y-adapter (I will just make a RCA cable with 2 in 4 out) to connect to the XD400/4 to use the amplifier as a L+R bridged. Right? So basically the XD400/4 needs a four channel input to run as stereo bridged?

From the XD400/4 manual:

"When a pair of the XD400/4’s channels are operating in bridged mode, the output will be in mono (only one channel). This mono channel can contain right channel only information, left channel only information or the sum of the information from both the right and left channels. In order to achieve one of these options, configure the inputs to that pair of channels in one of these two ways:

1) Left Channel Only or Right Channel Only Information: If you wish to send a left-only or right-only signal to a pair of the XD400/4’s channels, use a “Y-Adaptor” to split the single channel signal into both left and right RCA inputs. This option is useful when using a pair of the XD400/4’s channels to drive left channel speakers only and the other pair of the XD400/4’s channels to drive right channel speakers only.

2) Left + Right Channel Information: When bridged and fed by a stereo input, a pair of the XD400/4’s channels will automatically combine the left and right channels into a summed mono (left + right) channel. This option is useful when using a pair of the XD400/4’s channels to drive a subwoofer system or a summed mono center channel."

Yes use a y-adapter to keep the left and right channels seperated when bridging.

Thanks for posting

Thanks for posting

No problem, at first I was confused by what it was saying then I see that when bridged all you need is 2 channel rca. But if you want to keep the left and right channel seperation then use a y-adaptor.

I was actually looking at those amps yesterday myself.

Thanks. The XD series from JL are great amps imo. They do rated power cleanly.