Tube Power Amp Reviews

Two audiophile buddies of mine both own Rogue Audio M-150 monoblocks. I'd always been impressed with not only the sound quality of the M-150, but also its price. For $4495/pair, I thought my friends got a whole lotta amp for notta lotta dough. In this day and age, it's a rare and wonderful thing to get a pair of monoblocks, made in the US by a real audio company, that give you 150Wpc of tube power for under $5000. When Rogue came out with an update of the M-150, the M-180 ($5495), I thought it might be a good subject for my first full review in Stereophile. John Atkinson thought so too. I also thought it would be interesting to compare the M-180 with the very tube-like and almost identically priced Pass Labs XA30.5 two-channel amplifier ($5500), a sample of which I had on hand. (see my Follow-Uphttp://www.stereophile.com/solidpoweramps/pass_labs_xa305_power_amplifi…; in August 2009).

Step 1: Find something that works. Step 2: Use it. Step 3: Repeat as necessary, then retire.

Remarkably, I set out to audition the Hyperion HT-88 amplifier ($2800/pair) over two years ago, only to be confounded by shipping errors, miscommunications, and, in the end, a stealthily defective tube. I almost gave up.

When I attend Stereophile's annual Home Entertainment show, I rarely sit and listen to music for very long. Instead, I try to hit every room, press the flesh, find out about new products, and play a little jazz.

When I unpacked the Rogue Audio Atlas, I didn't know how much it cost. After examining its chassis of high-grade steel, its silver-anodized aluminum faceplate, its sleek and slightly rounded edges, and, above all, its two chunk-o'brick transformers—for such a little thing (a foot-and-a-half square by half-a-foot high), it's heavy—I guessed around five grand. Then I called Rogue Audio and learned that it retails for $1395.

In this hobby, nothing's for nothing. To get that gorgeous midrange, with its harmonic depth and inner detail, tube-amp enthusiasts are willing to give up some things in the bass. Tube folks put up with heat and occasional maintenance—routine or otherwise. To get the ideal middle, fans of single-ended triodes are even willing to shave off considerable dynamic range and settle for ultra-efficient speakers that often have limited response at the frequency extremes. Those who say nothing is lost by preferring tubes are in denial.

My stepfather wore only second-hand clothes as a child and never understood why anyone would deliberately wash the color out of his new dungarees. By the same token, the senior members of our hobby, many of whom recall with fondness the transistor's advent, don't understand why anyone would now wish to throw away their newfound power. Some people deserve to be blessed for their point of view, even as the world moves away from it.