Subwoofer Question on Placement.

I purchesed a new Descent-I sub from ML.IN a dedicated 2-channel system for only one sub where would be the best place to set it up?
If I put it in the middle behind the main speakers the sub will be firing directly into the audio rack with the preamp and my cd-player, Or will the corners be ok as close to the middle as possible?
Need some opinions please.

Mine sounds best to the left and slightly behind my left speaker,,thats a hard question to answer as every room may be diff.,,
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I find that the right or left wall - slightly in front of the left or right speaker works well in most cases. This way your sub is at the same distance to your listening position as your speakers...consequently transients should arrive coherently....important for correct souding percussion IMHO.
Trial and error. I found that moving my 80 lb. sub was a chore, but necessary. A Radio Shack meter properly compensated gave me a good idea about peaks and valleys in the frequency response. A small REL sub I have is designed for filling in below speakers running full range and setting the crossover to match the slope of your mains. Then you slowly turn down the sub volume until you can't really hear the sub. Most subs are turned up too much. It should be very subtle and "disappear". And, remember to have fun!!
Try placing your sub on top of an ASC SUB-TRAP and placement issues will become less of an issue... its an amazing upgrade for any sub owner, imho...good luck...