Steve Guttenberg/CNET

I first met Dan D'Agostino in the early 1980s when I was an eager young high-end audio salesman. D'Agostino's company, Krell, had amplifers that were big sellers, and I sold lots of them. I liked them so much I bought one, a Krell KSA 100 and thoroughly enjoyed it.

D'Agostino departed Krell in 2009, and started Dan D'Agostino Master Audio Systems not long after. His first amp with the new company was christened Momentum, and it quickly demonstrated D'Agostino upped his game. He never looked back.

He was in New York at Innovative Audio last week to demonstrate his ultimate design, the Relentless. I was there to listen to the amp and meet with D'Agostino. I've known Dan a long time, but I've never seen him this satisfied and happy.

As we discussed the Relentless, D'Agostino explained the goal for the amp was to build a perfectly balanced design, one where the positive and negative electrical sides of the circuit were identical. To accomplish this end he needed to design completely original input technology and output power stages with no global negative feedback -- everything about the design broke new ground.

The Relentless is the culmination of D'Agostino's life's work. He invested two years into the project, and he admits he wasn't completely sure how it would sound until he fired up the first prototypes at home. His biggest fear was that the Relentless wouldn't actually sound better then his already in production Momentum amps. Once he and his crew started listening they knew it was a truly special design, befitting its very special price, $250,000 for the pair of amps in the US, £250,000 in the UK and AU$449,995 in Australia. Of course the company offers a full line of somewhat more attainable electronics, all of them made in their Cave Creek, Arizona factory, with mostly US made parts.

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He wanted to challenge himself to build an extremely high power design, far beyond the amps he'd done before, so the Relentless can deliver 1,500 watts into 8 ohm speakers, 3,000 watts for 4 ohms and 6,000 watts into 2 ohms, that's incredible! Obviously that kind of power isn't required for "normal" high-end speakers, but Relentless customers use extremely insensitive speakers that require oodles of watts to really shine. Making ultra high power amps is one thing, making great sounding ones is something else.

D'Agostino emphasized the goal wasn't merely about brute force, his first priority was musicality, an amp that liberates the soul of music, and gives the listener goosebumps. Dynamics live and breathe over this amp, with the Wilson Audio Alexx speakers, my impression of the Relentless sound was that it's remarkably delicate and pure.

The Relentless is rather large, it's 22 by 11.5 by 32.5 inches (570 by 280 by 826mm), and it weighs a staggering 570 pounds (258kg). It's big, and trust me on this there are a lot bigger but less powerful high-end amps on the market. D'Agostino's old 1,000 watt per channel Krell Master Reference Amplifier amps were four times the size of the Relentless. Oh, and the Relentless is a mono amp, so you need two for stereo. His other D'Agostino amps are far more sensibly sized, and by ultra high-end standards affordably priced.

When he's not designing amplifiers...

D'Agostino loves to cook, so I asked about the parallels between cooking and designing amps, and he said cooking is like organic engineering with flavors and ingredients. Though he has pasta-making machines, he prefers rolling pasta by hand on a granite slab. The sensual aspects of cooking appeal to D'Agostino.

In 30 years of making pizza, he says he never made the same dough twice, for D'Agostino in the kitchen it's all about the feel and taste. He uses an electric pizza oven, but he's seriously considering building a brick oven at home. With food and audio, he's always trying to top himself.

The Dan D'Agostino Master Audio Systems Relentless is a statement design, and so is the price, it's $250,000. I assumed D'Agostino's customers were mostly Russian and Middle East billionaires, the sort of folks who buy $3,000,000 Bugatti Chiron sports cars. I stand corrected D'Agostino says half of all Relentless sales are in the US. Great sound has universal appeal.

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