No LP's, we didn't have access to a turntable.
Digital files fed to the C48 via USB, then spdif. These recordings are mine, I'm very familiar with them and have used them to audition many pieces of equipment.
The room is big: 30' x 25' x 11' at least and overall the system sounded incredible: absolutely had no problems filling up the room, accurate, loud, no distortion whatsoever at insane volume levels, very detailed and revealing. Except for what I perceive to be some brightness.
He's also running 3 Fathoms F112's. Thanks to the C48's ability to switch inputs at a touch of a button, we tried to see how the 800's woofers did by themselves vs. running together with the subs. Not even close!! Most the reviews I've read said that you don't need a sub with the 800's and so on. Absolutely not true. The 800's could not pressurize a room this size successfully. The Fathoms add a different dimension to the low end, it's unreal. We had them set to output at probably 20% of capacity and still, they complimented the 800's beautifully. Don't get me wrong, I am very impressed with the 800's and it's a lot of fun dialing this nice system in. Next step is to run REW.