Cam, I'd use an Axiom Full Metal Bracket instead of a shelf.

I think viewing angle is going to be important, depending upon the height of your plasma. Any chance you could put the VP150 above the TV and angle it down?

If you really must use a shelf, leave enough space behind for the wires/banana plugs/etc. Put the front of the speaker a little forward from the edge of the shelf.

I'm not helping am I?

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