Unusual 7.1 speaker placement

I am arranging the speaker placement of my 7.1 system and have a couple of questions in regard of the placement of surround back speakers:

1) The manual of my Denon AVR-988 (mostly equivalent of AVR-2808CI spec-wise) recommends 60 degrees whereas Dolby recommends 135 to 150 degrees for the placement of rear surround speakers.

Since the difference seems not marginal, I would like to hear your take on this issue.

2) The distance between me and the rear surrounds is going to be too short because, due to the size of my TV, I can move forward my couch only up to 50 centimeters/20 inches, and generally only when watching content that does not fill the entire screen. When I move forward my couch as such, the gap between the couch and the wall barely accommodates my rear surround speakers.

According to the below article, “one requirement for 7.1-channel surround is sufficient space behind your couch and listening area—at least 5 feet or more. If your couch is jammed up against the rear wall or you have a comparatively small room of less than about 2,100 cu. ft. (length x width x height), the addition of two rear surround speakers will not likely add significant improvements in envelopment, especially if you are already using Axiom’s QS8 or QS4 “multi-polar” surround speakers.” I should note that although I do not have such space, my room is large and my speakers are direct radiating.

http://www.audioholics.com/education...surround-sound

Under these conditions, do you think that it would be better not to use rear surrounds at all?

If you don’t think so, or assuming that I would want to rear surrounds nonetheless, would your answer to the first question be changed?

In all 7.1 diagrams I have seen so far, the rear surrounds are placed behind the most left and right of a 3 to 4 seater-couch. Perhaps I can place them not behind my sofa in a way that my side surrounds and rear surrounds are aligned??

3) If I lean my sofa against the wall, then would it be extremely implausible to use 7.1 where the angle between me and the rear surrounds would be 90 and the side surrounds will be a tad in front of and facing towards me?

Thank you!

PS. I will use all speakers at ear level.

No I did not. I am sorry if I mis-described. Thank you for your comments anyway.

Thank you, Craig.

If I insist on using surround back speakers (perhaps only when I move my couch forward and may be limited to 6.1 or 7.1 encoded titles), where would you recommend me to place the speakers in the attached diagram, considering that the gap between the wall and the couch will only be 50 centimeters/20 inches? To the red, blue or yellow box?

Although I placed the boxes to the left side of the diagram, please assume that I will apply the same to the right side for the right back speaker.

I should note that the distance between the center of my sofa and the left surround side and rear speakers can be at most 215 cm/85 inches, whereas I can extend the distance for right surround side and rear speakers as much as I can, though, I believe I should not do that in order not to lose equidistance.

That sounds reasonable.


I will use Aperion 5B bookshelf speakers. They are not bipole/dipole. All of my speakers are 5B, except the center is 5C.

In any case they will all be aimed at the primary listening position and at ear level as they stand on the same speaker stand with the exact same height.

I believe you meant you would use the yellow box in terms of the placement of the rear surround speakers and aim it to the primary listening position, right?

Also, would you place the rear surrounds to the yellow box if they were bipole/dipole? I guess you would place them differently as you asked the type of my speakers. The reason why I am asking this question is because I can use a friend's speakers if they would serve under my room's layout.

Sorry. I meant blue. Thank you.

Would dipole/bipole speakers further worsen the situation? Or would they be better than monopoles in my "least worst" condition?

OK so for the time being I will use my monopoles in a 7.1 setup only for 6.1 encoded Star Wars and LOTR EE blu-rays as they contain discrete sound for surround back channel and their aspect ratio allows for me to move my couch forward. Then I will put them to their packages for future use.

I may use them in future as surround back speakers in a permanent 7.1 setup if I move to a room where there would be sufficient space between my couch and wall. Or I can follow your suggestion of upgrading to PLIIz, including buying 2 more speakers for 9.1 system, depending on which room I will use them. Currently we have two living rooms, one is small and cosy, with L-shaped couch and a 42 inch TV. My surround sound system and my 52 inch TV is located in our bigger living room where we, for instance, host a dinner for friends&family/guests. It would not be proper to hang speakers on wall especially at that height.