The Mana is a fine blend of good looks and contemporary circuit design, even…
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Victor Tiscareno and Byron Collett of AudioPrism are known in audiophile circles for their complete line of power-conditioning products. (See Barry Willis' omnibus review in the December 1998 Stereophile.) Their intimate knowledge of the ever-capricious electrical supply has resulted in a series of front-end components bearing the company's logo. The flagship Mana Reference monoblocks, under consideration here, represent AudioPrism's collected wisdom and engineering savvy taken to its logical extreme.
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…
Sidebar 1: Specifications
Description: Monoblock tube power amplifier with switchable Ultralinear or triode output stage. Tube complement: eight 5881/6L6, four 6SN7, one Raytheon or WE 5842/417A. Bias: class-AB1 fixed bias with individual adjustment, 6dB global differential feedback (first stage not in feedback loop). Specified output power: 100Wpc into 8, 6, 4, or 2 ohms (20dBW), 115–130W at visible clipping (Ultralinear); 55Wpc into 8, 6, 4, or 2 ohms (17.4dBW) (Triode). Input impedance: 110k ohms single-ended, 200k ohms balanced. Voltage Gain: 26.5dB. Distortion: 1% THD at full rated…
Sidebar 2: Associated Equipment
Analog source: Judith Spotheim La Luce and SpJ turntable/tonearm, Koetsu Rosewood Signature Platinum phono cartridge.
Digital source: Forsell Air Bearing CD transport, Burmester 989 CD transport, dCS 972 Sample Rate Converter and dCS Elgar converter at 24/192, direct output to the amps or into the preamp.
Preamplifiers: Classé Omega, BAT VK-50SE, Burmester 808 Mk.V, YBA Signature 6 Chassis.
Loudspeakers: JMlab Utopia.
Cables: Synergistic Research Designer's Reference Discrete Shielding, XLO The Limited, TARA The One. Power cords: AudioPrism…
Sidebar 2: Measurements
Because of the Mana Reference's wide variety of configurations—four output transformer taps, ultralinear or triode output tube/transformer operation, balanced and unbalanced inputs—I carried out a complete set of measurements on the amplifier only with balanced input and ultralinear output. I did check some of the performance parameters in the other modes, however. But if no input or output modes are mentioned, assume it's balanced and ultralinear, respectively.
Before I did anything, I warmed up the amplifier at one-third power into 8 ohms for 60 minutes…
The phrase "the mystic chords of memory" comes from Abraham Lincoln's First Inaugural Address. Of course, larger issues than those addressed in this column occupied most peoples' minds just then. But it is nonetheless worthwhile for us to spend a moment or two thinking about how differently people experienced music in 1861, compared to how things are today.
In America in 1861, there was virtually no recorded music. If it wasn't live, you couldn't hear it. And once you heard a piece of music, you would never hear that exact same performance ever again. In 1861, music lived on in peoples…
Lincoln was not the only US political-historical figure with a musical side. Charles Gates Dawes, who later served as Calvin Coolidge's Vice-President, wrote "Melody in A Major," which became one of violinist Fritz Kreisler's favorite encore pieces, and was later picked up by Tommy Dorsey's big band. Dawes shared the 1925 Nobel Peace Prize for his work in rebuilding Europe after World War I.
In 1951, perhaps prompted by Dawes' death earlier that year, songwriter Carl Sigman decided that Dawes' "Melody" would be a great vehicle for some bittersweet lyrics. The result, "(Many a Tear Has…
Other orchestral recordings that still arrest my memory are Erich Leinsdorf and the BSO's phenomenal reading of Holst's The Planets (Deutsche Grammophon), von Karajan's Scheherazade for its solos by concertmaster Michel Schwalbé (DG, although Charles Dutoit and the Montreal Symphony's effort for Decca is also wonderful), Antal Dorati's of Dvorák's Symphony 9 (London Phase 4), Stokowski's unique, non-Ravel orchestration of Mussorgsky's Pictures at an Exhibition (London Phase 4), Rafael Kubelik's engaging disc of Dvorák tone poems including The Golden Spinning Wheel (DG), Sir Adrian Boult's…
Sidebar: John Marks' Mystic Chords
1) Linda Ronstadt: "Long, Long Time" (by Gary B. White); from Silk Purse (1970) and The Very Best of Linda Ronstadt (CD, Rhino 76109).
Ronstadt's vocal approach to this tearjerker is as much Grand Opera as Grand Ole Opry—here she achieved an intensity of passion and a degree of tangible naturalness that she never was to surpass.
2) Roberta Flack: "Jesse" (by Janis Ian); from Killing Me Softly (1973; CD, Atlantic SD 19154).
One of the most perfectly structured and elegantly written songs of the singer-songwriter era—"elegant" in…
Sometimes, a product review in Stereophile can breed additional reviews. Shortly after I reviewed the Audio Valve Conductor line stage in the July 2009 issue (Vol.32 No.7), I was contacted by NAT's US distributor, Musical Sounds: "Hey, if you liked the Audio Valve Conductor [$13,995], you'll love the NAT Symmetrical line stage at $8000! Would you like to review it?" Aside from Michael Fremer's review of the battery-powered NAT Signature Phono stage in the July 2007 issue, I was unfamiliar with this Serbian maker of tube electronics. But "Sure," I replied; "why not?"
Designing…