At 95 lbs, Dan D'Agostino’s 300W into 8 ohms, Momentum monoblock amplifier ($50,000/pair) doesn’t even come close to the weight of the big Boulders. Featured on the cover of Stereophile’s CES issue, the Momentum could be heard in many rooms at CES. This compact, energy-efficient design was driving the new YG Electronics Sonja 1.3 speakers ($106,800/pair). The resulting sound was dynamic, effortless, open, and had a wide, deep soundstage.