Background noise has nothing to do with sound staging. Noticeable noise, from the listening spot, during very low levels obscures the details. This noise is mostly quiet hiss. If the ambient noise in room is not very low, system noise may not matter.
I like the system noise to be inaudible, with my ear on the tweeter, at the highest volume level setting. Only then is the noise low enough, to not ever effect the low level details in music, IMO. This only happens with certain solid state equipment. Pure tube phono stages and LOMCs never reach this level, even on mint records.