Keith,
I can't really comment on the "Rush In Rio" CD because I haven't heard it. I watched the DVD and it sounded decent, although the crowd ambiance was mixed way too loud for my liking.
From what Jeff and Steve said, I believe the CD's problem originates from the substandard, even chaotic, live recording (I've pulled my hair for quite a few times when mixing bad live recordings!). Maybe there were too much leakage (drums and guitar amps leaking into the vocal mic; guitar amps leaking into the drum mics, house PA feeding back into all mics on stage etc.) all over the place on the multitrack tape/harddisk causing severe phase problems and they had to use extreme EQing (cutting lows and low-mids to get rid of the muddiness...overdone maybe?) and gating (shut a channel up when the instrument or voice is not sounding, but it all comes back once the instrument or voice starts to "happen", something like single coil buzz and hum coming at you when you start playing through a gate) on each individual track and way too much reverb and echoes in the mixing stage to smooth the whole thing out. To make up for the shortcomings in sound balance and make it LOUD, the mastering engineer had to, again, use heavy limiting to squeeze the thing, and use up all available headroom of the 1630 master or Exabite (DDP) master, at the expense of constant clipping. The result is a CD that makes you feel uneasy when listening.
Just my humble opinion.
