Integrated Amp Reviews

Back when gasoline had lead in it and amplifiers came with circuit diagrams in the back of the manual, there was an unspoken understanding that power meant weight. A professional camera was a Graflex Speed Graphic or a Hasselblad 1000F, built like a small battleship and nearly as heavy. Powerful car engines were cast-iron V8s with cylinders you could stick a fist in. And of course, serious amps had transformers that could double as boat anchors.

These days, amplifier design often emphasizes efficiency. Class-D amps in particular have come a long way. Many are terrific, and they're undeniably practical. But there's still something uniquely satisfying about a design that prioritizes timeless expression over economy of electricity or space.

The Pathos InPoL Legacy, a class-A design, is unapologetically massive and so gloriously overbuilt that moving it requires a tactical plan and a chiropractor.

From the 1088 establishment of the University of Bologna, the oldest university in the Western world, to the invention of the radio by Guglielmo Marconi in the mid-1890s, Italy has been at the forefront of innovation and artistic pursuit. Modern Italy stands as a testament to its vibrant past.

"The Italian Renaissance, which began in Florence in the 1380s, marks the first moment when Europeans stepped away from the traditional and medieval pious Christian view of man to embrace values and attitudes they had discovered through studying the culture of the ancient world," wrote William ("Bill") Adams, a former professor of Italian history, in an email. "Those values, belief in the dignity and worth of man, in human development through education which, having spread through Europe, led to the Scientific Revolution and the Enlightenment."

In 1996, Bill and I journeyed to Tuscany, where we stayed in a mountaintop castle nestled within the ancient walls of San Gimignano. Returning to Italy in the summer of 2024, I embarked on a tour with kindred spirits. Our travels took us from savoring perfectly al dente pasta in Rome to indulging in boot-sized portions of tiramisu in Tuscany. We also ventured into the Treviso countryside, where we toured the Unison Research (UR) factory. This is where I had my first exposure to Unison Research's S6 Black Edition Integrated Amplifier ($6999).

Audiophiles are often misunderstood as mere hobbyists; in fact they hold a profound reverence for sound. Japanese jazz kissas, where vintage vinyl, turntables, tube amplifiers, and horn speakers have drawn audiences since the 1950s, exemplify this passion. Western audiophiles share a similar fervor, though our pursuit of sonic perfection often manifests in a more discreet, almost monastic, lifestyle.

Shinobu Karaki, a 65-year-old electronics designer, is the founder and chief designer of Japan's Aurorasound. A music lover first, an audiophile second, and an aspiring jazz and classical guitarist, Karaki crafts phono stages, step-up transformers, preamplifiers, power amplifiers, and integrated amplifiers for his Yokohama-based audio company.

What's in a name? Denmark-based Gryphon Audio Designs laid down a marker when company founder Flemming Rasmussen chose that name in 1985. Browsing through the current Stereophile Recommended Components list, I only found one other manufacturer that utilizes an animal moniker. The imagery summoned by the use of the mythical treasure-guarding Gryphon seems appropriate; a hybrid creature combining features of the eagle and the lion, creatures of strength and speed—this choice underlines some of the aesthetics and performance Gryphon Audio has become known for. The handsome hardcover user's manual for the Diablo 333 simply states in gold "The Gryphon," along with a side-on profile of that winged lion-tailed creature, as a logo.

The Gryphon Diablo 333, a solid state, stereo integrated amplifier ($24,900 without optional DAC and phono stage modules), replaces the Gryphon Diablo 300, which was in production since 2016.

While there haven't been any follow-up reviews in recent issues of Stereophile, the January 2025 issue features further coverage of two one-box solutions that were reviewed in 2024—the Hegel 400 streaming integrated amplifier and the T+A R 2500 R multi-source receiver. All the user needs to do to create a complete audio system is to couple one of these products with a pair of passive loudspeakers.

The Internet of Things has arrived at the stereo rack. Many hi-fi systems are now connected to the wider world, controlled by phones and tablets. Complex front panels with many switches and buttons have practically vanished; those still around are retro pieces or style statements. Little front-panel touchscreens with complex menu trees have been rendered vestigial or at least redundant. Designers of receivers, integrated amplifiers, and DACs must now at least consider incorporating a streaming module and a device-control app. In certain component categories and certain price brackets, a built-in app-controlled streamer is now a key part of the value proposition, much as a tuner was back in the days of terrestrial radio.

The Hegel H400 combines the functions of an integrated amplifier, DAC, and streamer.

In 1989, I bought my second pair of Rogers LS3/5a's from a guy on Staten Island who had them hooked up to a Musical Fidelity A1 integrated amplifier. After playing the speakers for me, he began removing his zip-cord speaker cables and paused to show me how, at the amplifier end, his red-plastic Pomona Electronics banana plugs had partially melted from the A1's heat. We both laughed.

After it first appeared in 1985, the A1 quickly became famous for its hot top plate. The top plate got as hot as it did because it was used as a heatsink for the output transistors, which were biased highly into class-A. The A1's hot top made tabloid headlines, but for me it was its bold, sinewy, un-transistory sound and timeless, sharply drawn styling that distinguished it from cooler running Brit-fi competitors such as Audiolab's 8000A, Creek's 4040, A&R Cambridge's A60, and NAD's 3020.

Now it's back, priced at $1779, looking and feeling cooler than before.