Ryszard,

With a real powered sub that has a crossover built in - you don't build new y-cables.

wiring looks like this:

signal source L ---> subwoofer ---> behringer truth left
signal source R---> subwoofer ---> behringer truth right

Floorspace required: 13-1/2"W x 17-1/2"H x 15-1/2"D

That's pretty darned compact. 250W that you can tune right with the built in subwoofer.

The only thing you might need to do is chop off the connector of the cable and strip 1/4" length that you are sending to the behringer truth monitors so that they will work in the spring loaded terminals in the image on the listing. Is this making sense yet? No parallel path per side. Each side's signal to subwoofer crossover that is built in the subwoofer, and then the peeled off non-low frequency signal is sent to the monitor channel for that side.

I disagree that monitoring systems don't have subs. Not true. Many monitoring systems have been sold over the years that use subs. You can use the sub to handle both sonic and subsonic frequencies - your choice depending on where you set the crossover frequency and the upper frequency limit of the sub.

The 'Y-cable' is actually inside the powered subwoofer as the cross-over. No need to build it yourself. Did you know that the powered subs have the cross-over mids and highs available on terminals? That's where you connect the behringer truth monitors.

Shoot, most commercially available powered PA systems with subs work this way as well. The monster Mackie PA that we used at our last 'portable' church had both crossed over and full range OUTPUTS on the subs that then went to the mains which handled mid-lows to highs.

This is the way to handle your situation with the least fuss and expenditure and with a minimal footprint. I won't try any more to convince you any longer of that - but all you need to really do is hit that Polk Craigslist listing http://atlanta.craigslist.org/wat/ele/3135733426.html , and look at the photo of the input/output (inputs hidden a bit by the spring loaded connectors) panel on the subwoofer to understand what is going on. 250W of subwoofer power with the amp, with a user setable variable crossover, phase switch, etc. $95 - no brainer.

-Scott

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