“You have to open a door or window to let the pressure out of the room.”

If your room is small to even large if you are throwing over 90 db + pressure levels opening a door can be a good thing  for eventually room reflections  will create distortions and overwhelm the room ,it has happened to me and my room is 30x16x8 and I just sit 12 ft from the front of the speakers I can’t sit further back or I would  I have gym equipment and dresser. In front I open the door and the room sounds not as congested ,when the spl levels are under 90db which is most of the time playing rock in the mid 80db level then it it’s ok, I have Bass busters acoustic panels behind and to the fist reflection s to the side and wall to wall carpeting , no windows except at 30 ft away  , no matter how expensive the gear is your room has its limitations with hard reflections at higher spl levels.

Wife playing tennis this morning, so tested with the door open. Results were cleaner throughout, but certainly cleaner bass. I plan to test with REW, but strongly suspect I will have the same results as @rjduncan 

Great post… who knew. 

Now salt lake city has an open air concert stadium . So where do the waves go? It has recently been discovered that the brine shrimp in the great salt lake have increased since styx played there. I won't mention the band that decreased the population. I turned serius on the love channel now I have too many cats.retrospective prospective double blind non bias study just got accepted for publication funded by peta. Enjoy the music waves. Do we port speaker boxes and why? Is it an open door? 😃

Of course it makes perfect sense that it would change the sound, especially in the bass.  Kind of makes me think of bass reflex cabinet vs a sealed cabinet.  

What sounds better is up to you and the details.

@signaforce Glad to hear that!  I was curious a while back and got the REW software and a mic, and in addition, acquired some technical books to help me better understand concepts like decay, sound wave dynamics and resulting things like room nodes, etc.  I've had a lot of fun listening to, and then testing with the software, things like opening/closing blinds/drapes, doors, moving furniture and of course speaker placement.  Most all of it makes a measurable difference with the software.  Not all of Iit made differences I could notice with my own ears, however.  Or if I did, maybe not always positive differences.  But opening the rear doors to my room (which creates a 7-8 foot "hole" in the back or my room) makes an incredible difference, especially in the bass.  And importantly, I understand why that is given my measurements and study.  Good luck!