Why does bass have more “punch” when I stand up vs. sitting?


I have Rockport Avior speakers and I notice when I stand up the bass is slightly louder and has a little more punch than when I am sitting. This is with the same distance from the speakers. And the speakers are level with the floor. I do like the sound more when standing.  Has anyone experienced this?  Suggestions as to how to have the bass response while sitting as I do when standing?  
128x128lourdes
Room acoustic treatment is most important thing, and a small portion of Hi Fi enthusiasts takes care about it.
I always say - start treat your room at proper way, upgrade it in small steps adding absorbers and diffusers rather than selling the speakers to buy more expensive ones, or buying concert hall amplifiers to prove yourselves that I have bigger and stronger d.ck than my neighbor.
Just follow few basic things in your room treatment from people that know their business:

https://gikacoustics.eu/?gclid=Cj0KCQjwlOmLBhCHARIsAGiJg7nWjJmqN91NALm-aCYxJR0zlkci-s5K7B-NSf-KKc1zU...

https://ssteu.com/acoustic-tube-bass-trap-copy-2E_AUvgHRMDR4S77zrTGl

https://www.rspeaudio.com/ASC-IsoThermal-TubeTrap-11-p/asc-tubetrap-11.htm

Enjoy the sound

Regards
Klikoman


You are sitting in a bass null.  So am I, but since it's a family room and there's not really another way to situate the sofa, there's not much I can do about it.

Thank you all for not only responding but also for staying on point to my issue. I appreciate your taking the time to read about my issue and the time you took to respond. I will try to respond to all of you in one note.

 

NONOISE: My listening chair is a club chair that has some cushioning and it is about 8 feet from the speakers

LARRYi: I have been trying different speaker placements and do have tube traps. Per your suggestion I did move my listening chair back about 4 inches and it did help. I have been considering a subwoofer. I am not seeking booming bass. I want it to be natural and seamless with my speakers.

MILLERCARBON: My speakers are 62.5 inches from the front wall and 38 inches from the side walls.

MOTOKODUSANAGI: The speakers sit on rugs now and as mentioned above, I do have tube traps in the corners.

DWELLER: The platform you suggested sounds like a good idea. However, the speakers weight 200 lbs, and the base has a good size footprint

ATMASPHERE: As mentioned above, I have started researching subs, but have not looked at the Swarms. Thanks for the tip.

KLIKOMAN: Thanks for the idea of diffusers. I have visited the Gikacoustics site many times, but not the others you sent. I have no intention of changing speaker as I really like my Rockports and I am satisfied with my amp.

MTROT: Thanks for responding