Michael Fremer has posted a review of the Dan d’Agostino Momentum monoblock amplifier ($55,000/pair) at Stereophile. His conclusions:“Driving the big, efficient Wilson Alexandria XLFs, the steam-punk needles of the Dan d’Agostino Momentums’ power meters barely budged, no matter what I threw at them. Given their rated power output, they should have little trouble driving speakers of any efficiency or inefficiency, no matter how punishing the load. If their power ratings hold up against John Atkinson’s measurements (given who designed these amps, I have no doubt they will), the Momentums like low impedance loads. I’ve heard more clinically precise amplifiers, and ones that produced more digital-like black backgrounds, but, other than the darTZeel, none that could produce such a “meaty” well-proportioned, consistently enticing sonic picture. Dan D’Agostino’s Momentum is clearly his best design yet. With the darTZeel NHB-458, it’s one of the two most satisfying power amplifiers I’ve ever heard.”
You can read the full review here.