Chip, welcome. A rear-ported speaker should be positioned so that the ports have some "breathing" room. The distance can't be given precisely, but it's been said that at least 2" should be adequate.
A vertical speaker shouldn't be placed horizontally if it can possibly be avoided. The horizontal dispersion would be significantly poorer if it was used in that orientation.
Whenever a speaker is placed in an enclosure, care should be taken that it isn't recessed into the enclosure. The front edge of the speaker should extend a fraction of an inch beyond the enclosure to minimize reflections and refractions.
I have heard anything from don't place rear vented in an enclosed space like this, to the speaker needs 6" of clearance. Makes it difficult to decide, unless I could borrow the speakers and determined prior to purchase that they will work. What about side ported speakers- does the same apply here?
For the speaker height- this isn't as much of an issue as there are plenty of speakers that are under 11" tall, but again I have been told that this isn't optimal and should be avoided as you have stated.
thanks for the input
