I've not heard the Vitus but had the Quadrature Z in my system for a week or so. The Berning amp has the vitality, transparency and illumination of a fine OTL. (Won't debate whether it actually *is* an OTL). It revealed layers of harmonic nuance - I liked to say you could tell that Dusty brushed with the Ipana, not the Colgate. Taut, tonally fulfilling bass. Easily the fastest amp I've ever heard. Good luck - the comparo should be a lot fun and I'd like to hear your assessment.
David Berning Quadrature Z or Vitus SS-101
I've been using a Vitus SS-101 for some time and it's certainly a fantastic amp. I've been wanting to try a great tube amp that's not sloppy in the bass and i've negotiated the purchase of a David Berning Qaudrature Z. I will a/b test on my system and sell the one that loses the shootout. Any thoughts on what's the better amp?