You'll get more clarity with better subwoofage, imo. Everyone writes off good clean bass when they haven't heard it. I'm guilty too. It took me experiencing it to get it. Those subs you have leave some to be desired and you can do better. New amp money will get you some nice subs.
I had a pair of cheaper subs too and felt like I had plenty of bass, but it was mucking up my sound quality across the board and I didn't even know it. My experience was that my main speakers even sounded cleaner and clearer. Distorted bass is sneaky and doesn't smack you over the head like it does in higher frequencies. I didn't notice it until it was gone, and then it was like someone put glasses on my ears.
You're right, your room isn't huge and we aren't telling you to get monster subs. Just better performing, cleaner sounding ones. It was a real eye opener for me. SVS has been pushing their PB/PC2000s through their outlet to make room for the new pro series and the price is pretty nice for them right now.
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