Whats with all these Class D amps. My friends bring them over to my house and say look it weighs almost nothing and it will produce some crazy amount of power like 500 watts per channel. Then they will proceed that it should keep up with my Pass Labs X350.5. The class D does not come close with the most important part the sound quality. Next the Class D will make your ears bleed in the process. The flat tinny sound must be in style these days. All aside my friend has pair of ZU audio Omen Definitions and they sound extremely good with his collection of tube amps; 1) Modified Jolida 502B, 2)Manley Stingray 3)Cary 300B Integrated 4) Modified Dynaco ST 70 with a Dodd Audio Buffer Preamp. All those amps do a great job and hold a class of their own and still kill Class D as for sound quality. Buy decent tube amp and those ZU Omens will sing the way they were designed.