What affects front to back depth in room/ system?

@veerossi - thanks for those dimensions. I don't see any issues. You are kind-of close to the back wall, but that's way better than sitting in the middle of the room, where you would experience bass nulls. Your gear looks great to me, so next steps are probably room treatment, as others have recommended.

Working out how much treatment is needed and where to place it is not rocket science. A few measurements from your listening position using Room EQ Wizard and a calibrated mic (eg., miniDSP UMIK-1) will tell you just about all you need to know. Feel free to PM me if I can help.

I am fortunate to have a relatively large dedicated listening room which allows for proper distances from the walls, This, along with abundant acoustic treatment provides for an immersive experience. I also use a distributed bass array akin to the Audiokinesis Swarm and I find that it further makes an enormous contribution to soundstage and depth.

https://youtu.be/gcf1Hp_oAv4?feature=shared

I think the speakers have the most to do with it. Mind you I don't have a high-end system but when pitting kef r11's non meta against everything in the room at magnolia, one thing I noticed was that the kefs had an unusually deep sound stage..I wasn't listening for it, I just noticed it, and it was the first time I ever heard a deep sound stage and as you probably know all of the speakers are very close to the rear wall in Magnolia I ultimately chose them over theB&W 702s2s I have them set up in-between 2 rooms with about 12 feet behind them, using a Denon 4308, similar to the Marantz that they use in Magnolia, so nothing special.. the recording has a lot to do with it I found that with live jazz I can easily pick out the location of the instruments. Some many feet back,The whole sound is very layered.. and as one other reader had said, shutting your eyes makes a big difference especially at night.

@veerossi 

I consulted with Dennis at acoustic fields before I built my dedicated room. He seemed very knowledgeable but said I would need about 35k to build the room. That was out of my budget. He also said my speakers would not work in a room my size. I went with an acoustician recommended by Duke LeJeune of audiokinesis to design my room and am extremely happy with the result. 

You need to listen to Diana Krall all the time if you wanna listen to things with sound depth . Most of the time I find it's the quality of recording that makes all the difference in the world despite whatever equipment you have