I haven't listened to it yet (but I will tomorrow when I can listen on my monitors) but odds are that the OTB version is the one with the best transient response. If the "warmth" appears to be like something you could maybe achieve with an eq, i.e. less treble and/or a bit more boomy bass, then that's probably the ITB version.
I remember taking the PT vs. Neve test a couple of years ago. I was thinking: "Damn, digital is really ahead now when it comes to the sheer quality of the signal." What I heard was the clarity and openness and thought to myself that must be the digital "clean" sound and the warm and more "rounded off" sound must be the analogue thing that we used to call "pleasing to the ear"... Until it dawned on me that hey, would Mr. Neve really build anything that would treat transients that bad? Would you expect anything less than crystal clear and open sound with any transients coming from the microphones being passed right through from one of the most sought after consoles in the world?
Of course the clearest and best sounding of the two would be the console. I chose what I thought simply sounded like the best audio path as my favorite. And that turned out to be the Neve console.
Judging from the answers and their reasons in this thread my guess is that B is the OTB version. But I'll check it out tomorrow myself, I hope...
"Warmth" is an illusion created by the word itself and most of us confuse it with high frequency roll-off and muddy low mids and bass. Too bad, because a good analogue recording path actually provides just the opposite and is the sole reason why we go into so fine details with all this nice gear we're building here.
Why would you choose a MC33079 over a TL074 if it was that much better to convert the signal to digital as early on as possible?
Why do I fall in love with the extra clarity and punch in a Cinemag CMOQ-2S over a Lundahl LL5402 in the output of an 1176 if I actually favored the more blurred low mids and bass and believe that's the "analogue telltale"?
The answer is it isn't and I don't!
But why do I get confused be the digital realm adding this "warmth"? Well, sometimes high frequency roll-off is exactly what's needed on a mix and a bit of "mud" certainly CAN hold the buildingblocks together and you may very well find that pleasing to your ear...
But what if you don't want mud and roll-off? Or more or less of it?
Wouldn't you rather have the choice?
And here's where the camera zooms out, a hot chick hands me a soldering iron, I smile like Roger Moore used to and the voice over says:"Analogue - The choice is yours!" 8)