I got my amp 3 days ago, and I am already amazed by how good this amp sounds. I have it hooked up to my Grace sdac and and i listen to it on my monoprice m1060 and my fostex Tr40. My previous tube amp was the little dot mkIII, and I feel a big a big upgrade switching to the ZDT Jr. The bass especially sounds stronger, more define and precise. The sound as a whole sounds richer and warmer to me. Although I am not an expert in audio gear by any means, I would strongly recommend this amp, because listening to it makes me really happy.