AudioPrism Mana Reference monoblock power amplifier Page 2

The final Operate position, Auto-Mute, is interesting and convenient in that it mutes the audio and switches the bias on the output tubes into cutoff after one hour of no signal. The amps disengage the mute within three seconds of signal reappearing. The result is less heat and power consumption, and so longer tube life. As all other voltages remain up while quiescent, the amp is quickly ready to give of its sonic best.

I'm impressed—it's all well thought out and neatly implemented.

Sorcerer, thy name is Mana
Considering its overall character, the Mana Reference impressed me right away as the spiritual heir to the Jadis JA-200, two of which I once owned and used as my reference. This was especially so in ultralinear mode (the Jadis, too, is an ultralinear design). While the JA-200 uses massive hand-wound transformers and point-to-point wiring to scale the audiophile heights, the Mana does it with the intelligent fusion of traditional tube values and innovative circuit design and support systems.

Aside from triode operation's sweet highs, huge draughts of tonal color, bags of air and harmonic lushment—as if all that weren't enough—the bass proved unusually fine for something on the order of 50W or so. It was pretty stunning as long as the volume control wasn't cranked too far into the red—where K-10 likes to peg it! One memorable evening she bashed the woofers with "Looking Down on London" from Komputer: The World of Tomorrow (Mute 9047-2), a tribute to Kraftwerk that's more enjoyable than you'd imagine. The peppy, thonky bass line kept the whole sonic construct up on its toes, moving it forward with heft, power, and oomph. The midrange was delightful, full of air, detail, and smoothness, with a complete lack of grain. The highs were sweet and engaging without ever sounding rolled or euphonic. Vee vill dance now!

Triode also offered up more air and stunning palpability than I knew what to do with. The bloom, in every good sense of the word, was totally remarkable yet never overdone. Try Fascinoma (Water Lily Acoustics WLA-CS-70-CD), Jon Hassel's striking new release, engineered by Kavi Alexander and featuring Ry Cooder, Jacky Terrasson, and Ronu Majumdar. "Secretly Happy" left me...well, secretly happy deep inside whenever I listened to it. The ambience and air were delicious, and the huge soundstage wafted out like a bedsheet in the breeze to settle gently over the listening chair. The haunting, mysterious tones and rhythms of the music developed into an Audiophile Encounter of the Third Kind: Contact!

But triode mode eventually lost its grip when I cranked the volume to a critical mass of stomp and drive. The onset of max headroom made itself known primarily in the bass, which became fat, congested, and way overripe. Switching to ultralinear kept the big, lightweight sawndwich-technology woofers of the JMlab Utopias under much better control right out to and beyond the legal posted limit. Okay, not like the giant VTL Wotans or practically any of the hulking, high-power, solid-state giants we've auditioned lately—but still low frequencies of an admirable quality.

When spinning such overdrive bass masters as Leftfield's Leftism (Hard Hands/Columbia CK 67231), I didn't even bother with triode mode. Some recordings are made to be played loud, and this baby is one of them. You might say it's a combination of Ladyship Black Mambazo and Art of Noise, with hefty handfuls of trip-hop and ska thrown in—high-voltage world music, if you need a label. The bass was big, chunky, and moved a lot of colorful, vibrantly charged air. The leading-edge transient information, even down below, was beautifully rendered in the way tubes do so well. It seamlessly blossomed into a harmonically rich and fully pitch-differentiated lobe of acoustic energy, dying back into the noise floor's dusky embers. Not as deep and tight as the aforementioned hugely muscular power plants, but still entertaining, evocative, and extremely palpable.

Let's turn to Alternesia (M•A Recordings/Series Momentum M3), composed, performed, and recorded by Stereophile's very own webmaster, Jon Iverson. It's spiritual, ethereal music with dollops of Loop Guru and world-music influence. Running in ultralinear on the 4 ohm taps controlled the deep and abiding bass produced by some of Iverson's massive collection of Balinese instruments.

And the midrange? Don't ask. Last year, while visiting JI and his (far) better half, Corinna, on the Left Coast, Kathleen and I wriggled in pleasure to the sweet, vibrant tones produced by the beautiful Balinese instruments in the music room. Chez Ten, that bell-like, captivatingly harmonic acoustic developed in practically the same way. Especially in triode, the decay into the noise floor was jaw-dropping. Damn, these AudioPrism amps sounded good.

Female vocals were a sensual delight in either mode, though triode was a good deal more seductive and sexy. Listening to the recent Cassandra Wilson CD, Traveling Miles (Blue Note 8 54123 2), or Sara K.'s fab new No Cover (Chesky JD185), proved revealing and viscerally enjoyable. I noted that while ultralinear sacrificed a certain bloom and ambient decay and sounded slightly drier than triode, the additional power was just what the JMlab Utopias needed to fully develop the soundstage, and especially the acoustic bass. There was a certain precision evident in ultralinear that served to improve the focus quite noticeably. I didn't miss it when enjoying the rounder, less sharp-edged imaging and tonal plushness of triode mode, but I appreciated it when I switched back. Strangely, while more focused, ultralinear was somehow less palpable than triode! But either mode delivered a huge, well-populated soundstage.

How about the boys? Try Mighty Sam McClain belting it out on Soul Survivor (AudioQuest Music CD1053). The album was produced by Joe Harley, of course, recorded in analog at 30ips direct to two-track, then mastered by Bernie Grundman in Sony's Direct Stream Digital process, everything wired up with AudioQuest cables. The result is, simply put, magnificent. Mighty Sam does me righteous with "When the Hurt is Over." You just have to experience the way he warbles "Baby you hoit me." My notes: "His intonation is amazing, the deep feeling in his voice, the pain and the hurt, the longing echoed by the delicate, low-key guitar work. Unbelievably 3-D and palpable, the air and smoothness are remarkable. There's some quality of acoustic seamlessness that DSD gets right that goes down to what seems like the molecular level." And this nugget from Joe Harley's liner note: "Performing for Sam is not about 'showtime,' it's about reaching deep within and giving a piece of himself every time." Well, you can hear it; this is one damn fine recording. And this is one damn fine amplifier system through which to experience the richness and meaning contained therein.

Mana from heaven
Overall, the AudioPrism Mana Reference proved less powerful and transparent than the tour de force that is the (similarly priced) 845-powered Nagra VPA. On the other hand, the Mana Reference is certainly more romantic and colorful than the Swiss amplifier, with more roundness and body to the imaging and more texture and velvet throughout. My sample pair always proved perfectly engaging, and a joy to experience music through. They deployed a lush midrange, a powerful and fulsome bottom end, and a sweet-natured, airy treble that seduced eye and ear alike. Best into a fairly efficient speaker (88dB sensitivity and up, I'd guess), they're sure to bring musical delight to any lucky owner's system.

I recommend the AudioPrism Mana Reference most vociferously to all tube-friendly audiophiles (footnote 1). And, given its easy-to-live-with nature, I recommend it as well to all of you who haven't so far considered tubed amplification. It was a bummer sending them off to Santa Fe for measurements.

Footnote 1: A revised version of the Mana Reference was subsequently available from Mark Levinson's Red Rose Music as the Model One.—Ed.
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