Tube Power Amp Reviews

Tradeoffs? When I listened to bassist Christian McBride and the late, great Billy Higgins set the groove on John Scofield's "Heel to Toe" (from Scofield's Works for Me, Verve 314 549 281-2), the sheer physical presence that ultralinear mode imparted to McBride's bass was intoxicating, as was the brilliance of Higgins' cymbals. All was conveyed in natural scale, never larger than life—a believable acoustic. However, while there were plenty of soundstaging cues and small details in ultralinear, listening to the same track in triode mode gave me a more palpable sense of air and transparency—with a softer, more textured depiction of Higgins' ride cymbal—while conveying more than ample rhythm and pacing.

Listening in triode mode to Patricia Barber's "Pieces" (from her newest album, Verse, Premonition/Blue Note 5 39856 2), the singer's dark, hypnotic alto was perfectly centered, suffused in a deep amber glow. Meanwhile, in another frequency domain of engineer Jim Anderson's brilliant mix, the Magnums maintained this critical vocal balance while fleshing out the complex room cues conveyed by Neal Alger's holographic electric guitar. And I've never heard another triode circuit convey quite the depth of tone and physical impact that Anderson and drummer Joey Barron elicit from his tiny titan of a bass drum—tight and tuneful, yet ringing like a gong.

However, it was in listening to the varied timbres, aquatic textures, and supple touch of pianist Jean-Yves Thibaudet, on his hypnotic recital The Magic of Satie (Decca 289 470 290 2), that the true grace, grandeur, and transient impact of the Rogue's triode circuit shone like a beacon. Sans the ingratiating midrange plumpness and happy gas of ultralinear mode, the piano just sounded more like a piano in triode, with greater clarity and transparency, and a profusion of harmonic details illustrating the inner workings of the concert grand. Triode also offered a more accurate take on this recording's distant, romantic perspective and the piano's interaction with this gorgeous acoustic space.

Comparisons
In a series of head-to-head comparisons with my long-term references, a tubed Mesa Baron ($4500) and a hybrid tube/solid-state Musical Fidelity Nu-Vista 300 ($5400 when last available), I used as my reference operatic diva Renée Fleming's remarkable Bel Canto (Decca 289 467 101-2). In "Era desso il figlio mio," from Donizetti's Lucrezia Borgia, Fleming hits and holds a conclusive, convulsive high E-flat with all the pedal-to-the-metal, transducer-frying bravura of Louis Armstrong on "West End Blues." I've never before heard singing like this. Since getting Mesa's "tri-tube" mod, the Baron's mids are smoother, sweeter, and more alluring with a set of EL34s than they were with 5881s, yet the amp still retains incredible speed and slam. A brighter top end and brassier upper mids give the Baron a sparkling, lively, bristling character.

But in adding harmonic artifacts to Fleming's upper register, the Baron was nowhere near as smooth, refined, and forgiving as the Magnum. The Magnum's mids sounded more effortless and subjectively neutral than the Baron's, a little drier and more laid-back on the top end, with snappy, tuneful, weighty bass—the Magnum M-120 conveyed all the nuances and heady dynamics of Fleming's phrasing with admirable character and accuracy.

I then put the M-120 head to head with my Nu-Vista 300. My notes: "The Magnum excels in the mids, which it portrays with a warm, smooth, layered character, while the Nu-Vista excels in the frequency extremes, with a cool, reserved style of midrange depth; a clean, true-blue low end and gobs of natural harmonic detail on top." The Nu-Vista excelled at delineating Fleming's voice amid a welter of orchestral details, but seemed a tad laid-back compared to the juicier, more vivid Magnum.

Conclusions
The Rogue Audio Magnum M-120 tube monoblock was so remarkably smooth, clean, warm, detailed, and dynamic that it rarely drew attention to itself with anything that sounded blatantly "tubey." Over time, I learned to more clearly apprehend its dry, laid-back tube sound, but I'm still surprised how much this monoblock put me in mind of classic 1980s solid-state designs from the likes of McIntosh, Luxman, Kyocera, and Hafler.

The Magnum M-120 managed to convey the best aspects of solid-state and tubes: while the instrument placement, transparency, and frequency extension might suggest solid-state, the depth of soundstaging, the wealth of harmonic detail, and the midrange layering were dead giveaways that tubes were in the circuit. At only $2395 for the Magnum Ninety-Nine preamplifier (review next month) and $3495 for the Magnum M-120, for less than six grand you, too, could be indulging in the audiophile lifestyle—with enough left over for hundreds of CDs and many a good bottle of wine with which to toast the proscenium arch and the enduring glory of two-channel tubed audio. Glow on with your bad self.