I finally bought something to drive the Mackie 1400i that I have. The PreSonus DigiTube Works like magic. A tube to warm things up, a flexible EQ, loads of headroom, digital out with clock option either way for my PC. I couldn't be happier. I didn't buy the rack adapter, I use industrial strength velcro and stick it to the top of my router so I can easily take it upstairs to my PC w/o having to unscrew anything.