"I was immediately impressed by the warmth and weight of the overall sound; the strong and clear bass, plus the sweet richness of Joni Mitchell's voice. The dense layering of background vocals and synthesizers was amazing. I sensed the relaxed ease and fullness you get from good tube designs, but with the immediacy and detail found in the best solid-state models.
The combination of responsiveness, transparency, and a certain relaxed ease makes the 404 Reference musically rewarding to listen to.
I reckon Moonriver Audio's 404 Reference must be one of the best integrated amplifiers currently available. It delivers an outstandingly clear, dynamic, and full-bodied sound, with great timing, plus levels of clarity and refinement that few rival regardless of cost approach. I absolutely loved it. [...] A veritable wolf in sheep's clothing, it offers a monstrous musical performance".