Ok, so you have the speakers along the longer 25' wall, making you sit the short distance? I believe this is how Dunlavy recommends. And, from my experience, this should sound better overall with this arrangement (all things balanced and considered of course). However, if I read you right, sounds like, yes, one speaker is in a different acoustic space form floor to ceiling...This is a tough one, and certainly not symetrical in the bass modes from floor to ceiling, between the two speakers balance wise! However, overall, your still going to get much better sound throughout, keeping the speakers on the long wall...no, I wouldn't put em on the short wall in your room!...it'll bring too much constriction and blurring, not to mention much much added coloration and reflection challenges from the side walls that way.
So, what to do...Yes, I think much of your challenge in the bass is the different ceiling heights above your speakers! The bass response will be inherently different, do to the different dimmensions of boundaries the speakers are in. I think you should experiment around with different speaker possitions a bit. Perhaps measure, with bass test tones, with a sound level meter to see which speaker is the flatest and most balanced over all in the possition there currently in. Then, try moving the speaker that seems to be off more in balance, until it balances better with the other speaker!...YOu should then be getting better bass response overall! I think you'll be adressing a bigger fundamental issue with your system, than simply adding bass traps. Yes, I'd still think you'll most likely get some good worthwile improvements, and would recommend you giving the corners some treatment...but not after dealing with the single most important aspect of your sytem set-up...speaker location (and seating location)! Good luck
So, what to do...Yes, I think much of your challenge in the bass is the different ceiling heights above your speakers! The bass response will be inherently different, do to the different dimmensions of boundaries the speakers are in. I think you should experiment around with different speaker possitions a bit. Perhaps measure, with bass test tones, with a sound level meter to see which speaker is the flatest and most balanced over all in the possition there currently in. Then, try moving the speaker that seems to be off more in balance, until it balances better with the other speaker!...YOu should then be getting better bass response overall! I think you'll be adressing a bigger fundamental issue with your system, than simply adding bass traps. Yes, I'd still think you'll most likely get some good worthwile improvements, and would recommend you giving the corners some treatment...but not after dealing with the single most important aspect of your sytem set-up...speaker location (and seating location)! Good luck