has anyone read the Digidesign's white paper " 48 bit mixer"? the link is below: http://akmedia.digidesign.com/support/docs/48_Bit_Mixer_26688.pdf as for some points, I'm arguing with a local Pro Tools HD user, and we can not persuade each other. I have asked these questions in Digi's forum, but official response is very slow. to make things simple, I have these question below: 1. what's the resolution of HD'S internal bus? I mean audio bus. someone thinks that as Pro Tools' MASTER FADER can be connected with internal bus and receive data from internal bus, and MASTER FADER is a 48-bit mixer, then the internal bus is a 48-bit bus. He thinks that the MASTER FADER of Pro Tools HD functions like a master fader on a analog console, then the bus the MASTER FADER connected with is a master bus, and this master bus shoule have the same resolution as the MASTER FADER. 2. if say, set a audio track's output to internal bus 1, a aux track's input is bus 1, and set a MASTER FADER track's output to bus 1. then which one of the descriptions of the signal flow is correct? A: audio track outputs to bus 1 first, MASTER FADER receives data from bus 1, and processes the signal as needed, including level adjusting, then output to aux track. B: MASTER FADER receives data from audio track, and processes the signal as needed, including level adjusting, then outputs to bus 1, the aux track receives data from bus 1.