Probably not what you want to hear but I think you should get properly sized stereo speakers for your room. Start there. It sounds like your current speakers are not up to the scale of your room.
Next, find the right location for those speaker and then treat the room. I don’t mean use crazy amounts of acoustical treatment. You can do a lot with very simple choices you make with existing furniture/art placement. One compromise my wife makes is we have no glazed picture frames in the living room. All the art on the wall is sculptural or framed oil paintings...some framed textile art. We have a 9x12 Persian rug and carefully placed furnishings.
It does not look like a listening room and isn’t perfect. But I get slamming bass and holographic soundstage in my listening position. No need for a sub.
I own two subs that are put away. Same issue: constant adjusting of the bass levels. In fact the imaging improved without them. My stereo amp doesn’t need to compete with the powered subwoofer’s transformer.
When you dial the main speakers in...then dial the subs into the mix.
I can’t imagine that a single 10-12” sub wouldn’t suffice for a room of your size. But I tend want subwoofers to just ‘fill in’ what’s missing. Some people like room shaking bass.
Next, find the right location for those speaker and then treat the room. I don’t mean use crazy amounts of acoustical treatment. You can do a lot with very simple choices you make with existing furniture/art placement. One compromise my wife makes is we have no glazed picture frames in the living room. All the art on the wall is sculptural or framed oil paintings...some framed textile art. We have a 9x12 Persian rug and carefully placed furnishings.
It does not look like a listening room and isn’t perfect. But I get slamming bass and holographic soundstage in my listening position. No need for a sub.
I own two subs that are put away. Same issue: constant adjusting of the bass levels. In fact the imaging improved without them. My stereo amp doesn’t need to compete with the powered subwoofer’s transformer.
When you dial the main speakers in...then dial the subs into the mix.
I can’t imagine that a single 10-12” sub wouldn’t suffice for a room of your size. But I tend want subwoofers to just ‘fill in’ what’s missing. Some people like room shaking bass.