Geez, I feel like I live in this forum these days... I borrowed a friend's preamp to try with my PUB - it's a Presonus Digi Tube with 3-band semi parametric EQ and a bass rolloff. It sounds ****ing great, and gives me a lot more clean volume than the Raven Labs unit, and with the bass rolloff feature, I'm not making the 8" driver of the PUB get all "poofy" at higher volumes. I'm just curious what other 1/2 rack pres (don't want to carry anything bigger) are out there that I might try before deciding which one to buy. The bass rolloff is a must, and multiple parametric bands is on the wishlist, although is not a must. What other units are worth looking at within these guidelines?