If you want some power, I recommend the dna over the pass labs. It's a better amp for rock. The pass labs is better for quieter music. I used to own the dna1revaGold and the pass labs aleph 2. The pass labs had a more pure sound with amazing clarity, but did not have anywhere close to the power of the dna. I was driving ap virgos which are 89 or 90 db efficient. A stereophile article a few months back (nov 00) had a review of the dna 225. Rubinson remarked that it was pretty close to his old dna1revA. He said it was pretty much a toss up for sonics. I found that hard to believe given the superior parts quality of the dnaRevA.