low frequencies

the key is: those speakers, in that space, at that location

..........................................

I suggest: Get thee a simple Sound Pressure Meter, tripod, set at ear height at listening position

https://www.amazon.com/BAFX-Products-Pressure-30-130dBA-Warranty/dp/B00ECCZWWI/ref=sr_1_4?crid=1BZ6BV6ZMIG39&keywords=sound+pressure+meter&qid=1686325343&sprefix=sound+pressure+meter%2Caps%2C73&sr=8-4

next a test cd with individual tones. Note: I scanned several Stereophile Test CD’s, others, none of them have the full range of frequencies this test disc has (29).

https://www.discogs.com/release/7290000-Various-Amazing-Bytes

you will know how flat of a frequency response your speakers are producing, IN That Space, AT that location.

Next, try new positioning and different toe-in, measure the differences.

Amazing Bytes is hard to find, and expensive, I can find a used copy if interested.

TY for the suggestions DILL, The distance is 10ft ear-tweeter distance. Funnily enough I have moved the couch back another 2 feet and bass is sounding much more full. Polarity is all good😎

AM Acoustics room mode simulator is a great place to start. Look at the lowest modes and try to keep both your speakers and listening area out of them.

After that, it's good to measure to see exactly what your problem is. 

James633 thanks for sharing those thoughts. You have a lot of experience which is always nice to hear about. I was able to get much better sounding bass from a seated listening position by putting the couch further away from the speakers. Now at 13 ft from the tweeters and 3 ft 6 in  wall behind me. I think it was a bass null where I was before. 

Velocityofhue,

I am glad it worked out with a relatively simple fix. Room boundary interference is a frustrating one that can make great equipment sound bad. Moving the seat is 100% a practical solution that works if you have the space.

the 3.6’ (assuming driver face) technically makes a dip at 78hz. Closer to the wall will cancel higher and farther will cancel lower. I think thiel recommends a minimum of 3’ from the front wall which would make a dip at 94hz off the front (other boundaries matter too and can even it out or make it worse, really need to add all of them up and average them). Anyway 3’ works pretty well when not using subs. Less is actually better for the bass. I have found as close as 30” to be fine. As you get closer you lose some of the depth to the soundstage. Pushing them back just a bit might improve your bass a bit more as 80hz and down is critical for bass impact.

I typically use subs and in my main systems I pull the thiels 5’ off the front wall but crossed over at 60hz to sub which fixed the null the 5’ distance caused. Without subs I like to stay 39” or less from the front wall or more than 7.2’. 7.2’ into my room is pretty awesome but my kids run around the speakers and I can ’t deal with it lol.

Boundary calculator here if you want to see where the nulls are in your room.

http://tripp.com.au/sbir.htm