Soundstage........

in audio, what in the system gives us the soundstage ?        I ask this as when I had the system in the living room I had one system that was :

anthony gallo 3.1's
edge amp
Belles 21a preamp
Technics 1200 mk2 w / AT 150 cart
bellari preamp
Synergistic Research sp cables, various low end IC's

and that system had everything ....soundstage , separation, detail.....and was enjoyable to listen to.       got out of the hobby for a bit and when I got back into it, I went with this system :

Magnepan 2.6 qr's
w4s mono blocks ( 250 each )
Lector Zoe preamp
PS audio phono preamp
Technics 1200 mk 2 w/ AT 150
Morrow Audio sp cables and various low end IC's

sold that system and had the chance to move the next system from the living room which had the cathedral ceilings,into  what used to be the master bedroom.....and now have a room that is good size 17 w x 21 l  8 ft ceilings and went with this the first time :

Magnepan 3.6r
Krell amp
Audio Research Ref. 2 mk 2 preamp 
Sim audio lp 5.3 phono preamp
Acoustic Zen sp and IC's
VPI HW-18 MK 2 w/ Moerch arm / Ortofon 2m Black

the Magnepans were way to big for the room and didnt like the AR preamp as it just didnt sound good....sounded cold due to the 6h30 tubes ( others may like it, but I didnt ).......sold the speakers, amp and preamp  and  ic cables and went with 

Tyler Acoustic Halo 2 speaker
Maker Audio G-9
Belles Aria
Sim Audio 5.3 phono
vpi  hw 18 mk 2 w/ Moerch arm / Denon 103 cart
Acoustic Zen Satori sp cables, KCI silkwork IC

this system is very  clean sounding and you can listen to it for hours and never get tired of it......but I just dont have the soundstage like  I did when the system was in the living room.        Room is treated with panels, have moved speakers in / out  / up / back, etc....and same thing.....       

So is it the room that ( cant think of the word, ) controls the soundstage or is it the preamp, the turntable / cart ?