Plaser,
In case you did not want to spend the extra money for the sub controller or are unhappy with the results, here is what I found useful when setting up subs. Probably you have already done all that and are happy. In that case just ignore me, if not, perhaps I may be of some use.
1. Place the sub, just as Mapman has suggested behind one of your main speakers in to the corner of the room.
2. Get an LP or a CD with steady really deep bass. The Rel people suggest here the "Sneakers" CD, film music composed by James Horner on Columbia. You can find that on eBay usually for little money. Use track four, which has a timely evenly spaced deep bass drum. Play your system at normal levels with the sub powered up and play around with the phase switch. Ignore the midbass music on the disk, just listen to the really deep bass drum and find out the loudest setting at either normal or inverted phase. Once you've found that, stick to that.
3. Next move the bass unit a few inches to and fro on an imaginary diagonal line through your room aimed at the opposite corner to where you've placed your bass unit. Have a friend at hand to listen where the bass drum gets loudest. This is probably the best spot for your sub.
4. Next settle for the right X-over points. If at all possible run you main system never ever through your sub's X-over. It practically always ruins the sound. To find out where to best let the sub cut in and at what slope, if the latter is possible with your unit, familiarize yourself well with the the sound of your test cut on the cd, WITHOUT the sub first and then experiment with the sub switched on. The sub must not interfere with, cloud or blot out in any way tjhe subtle information in the music on the disk, but be clearly heard when the bass drum is put into play. With the Sneakers cd this can be achieved very easily if you listen and have a friend fiddle with the X-over points. I've had very good success with this method, which also the Rel people use.
Good luck and happy listening,
Detlof
