Something funny happened to me the other day. I was mixing, as one does, and I noticed the tunes I’ve done with live takes sounded more holographic, than the ones done completely in the box. Not talking about the music composition, so much as the sound quality it’s self. It just sounded more real somehow. It wasn’t limited to acoustic instruments either. Even very artificial instruments, sounded different. A difference that was separate from WHAT sound I recorded. It seemed to only matter that the sound WAS recorded, instead of constructed purely digitally, having never left the computer for any reason.
I realized a significant part of this effect was due to background noise. Not having the best of the best equipment or situation to record, there’s a little, what used to be called “tape hiss” in the background. Basically low level white noise. From what I ascertained, the reason low level white noise makes sound more 3 dimensional, is simple. In the real world there’s always natural background noise. Even in a dead quiet field in the middle of nowhere, if you listen, there’s light background noise. Even if you are in an anechoic chamber, you will still hear it, because you are a living thing, full of energy, motion, movement and squishy things. Well unless you are dead. Odd place to die. In an anechoic chamber that is.
Anyway, the background noise gives the subconscious a more real life context to what it's listening to. The subconscious notices when that background noise is absent in music and therefor makes it sound more artificial. I guess this is perhaps why a lot of mastering plugins these days have a noise knob, so you can add in a that little “imperfection” that we were convinced was a bad thing back in the day before digital audio. Yes it’s true, digital audio is still a very new thing in the grand scale of musical history.
Background noise, liken to natural harmonics and saturation, in a way, gives music a subtle but noticeable and (if done correctly) very positive property. Making for a more holographic sound.