I see this question, or ones similar to it often - suggest speakers that sound good close to walls. And there's a lot of confusion in the answer often.
The short/simple answer is all speakers will be compromised in a near-wall situation. Every speaker will suffer a performance hit when close to walls because of relatively high amplitude reflections causing summation/cancelation resulting in a less-flat overall response. If near wall placement is a requirement, it's something you have to live with.
A couple things that may improve the situation:
- How is the speaker tuned? Many bookshelves tune a bit higher than optimal to give a hump in the bass response, and the impression of having more bass than there really is. In a near wall placement, that's the LAST thing you want because the bondaries will further boost the bass resulting in an overly fat and tubby sound. What is optimal is an Extended Bass Shelf alignment. Instead of explaining what that is, google if interested. But result of an EBS alignment + near wall is much closer to a flat end result.
- The closer a speaker is to boundaries, the more important it is for the cabinet to be completely dead. The walls will reflect the sound of those resonances just like they reflect everything else, the closer the wall is, the higher in amplitude those reflections will be when they reach the listener.
- Port placement is NOT a huge issue. With smaller bookshelves using 5-6" woofer, they just don't move all that much air. In that case all you need is 4-6" of space from the port opening and the closest wall. With larger 7" woofers you need a bit more space, but still only 6-8" is plenty.
- Put some 4" thick absorption panels directly behind the speakers that extend at least 1' past the speaker boundaries, thicker and bigger if possible. If you can control the rear wall reflections, it can help mitigate the negative impacts.
Hopefully that helps. Unfortunately nobody tells you what kind of bass tuning they're using, such as the EBS I mentioned above. Knowing that would help customers make an informed decision.