Along with exemplary top-to-bottom "attack," the Premier Twelve portrayed decay with equal propriety, resolving low-level information…
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The Twelves always sounded confident and in control—tonally, spatially, and temporally—particularly at the frequency extremes. On the bottom, both acoustic and electric bass sounded tight yet supple, and totally "in character" tonally. On top, the Twelve's transient performance was faultless, portraying cymbal crashes with the crisp, splashy shimmer you hear live. On good recordings, strings bristled with energy, yet never sounded hard or unnaturally edgy.
Yet when I switched from the C-Js to the VTLs and replayed Neil Young's "I Am a Child," the VTLs disappointed—they slowed the pace, took some snap off the snare and kick drum, and reduced the delineation between the images and the ambience behind. Moving to Gershwin's Concerto in F, though, the VTLs better suggested the hall, and offered a slightly more diffuse presentation that some may find more akin to being there live. As one manufacturer said to me about an update of an unrelated product, "You know what? I like the original version better. I go to a lot of live concerts, and live, you…
Sidebar 1: Specifications
Description: Vacuum-tube monoblock amplifier. Tube complement: one 5731, two 6FQ7, four 6550. Maximum power: 140W into 4 ohms (18.5dBW), 30Hz-15kHz, at no more than 1% THD or IMD. Frequency response at 10W: 20Hz-20kHz, ±1dB. Hum and noise: 98dB below rated power. Sensitivity: 900mV to rated power. Input impedance: 100k ohms.
Dimensions: 17.5" W by 7.25" H by 15.25" D. Weight: 51 lbs.
Serial numbers of units reviewed: 6101307, 6101308.
Price: $6990/pair. Approximate number of dealers: 70.
Manufacturer: Conrad-Johnson Design, Inc., 2733 Merrilee Drive…
Sidebar 2: Associated Equipment
Analog sources: Simon Yorke turntable; Simon Yorke, Graham 2.0, Immedia RPM2 tonearms; Lyra Parnassus D.C.t, Transfiguration Temper, Koetsu Urushi, Crown Jewel Special cartridges.
Preamplification: Ayre K-1 preamplifier; Audio Research PH3SE, Pass Aleph Ono phono sections.
Power amplifiers: VTL MB 450 tube monoblocks.
Loudspeakers: Audio Physic Virgo, Sonus Faber Concerto Grand Piano; Audio Physic Rhea subwoofer.
Cables: Yamamura Millennium 6000, Cardas Golden Cross, Cardas Neutral Reference, Electra-Glide interconnects; Yamamura speaker…
Sidebar 3: Measurements
Following its preconditioning test, the Conrad-Johnson Premier Twelve was hot—typical for a tube amplifier. The bias was found to be slightly off during the distortion measurements, was recalibrated, and the prior measurements were rechecked to ensure that the results had not changed significantly. (Except for the distortion, they had not.)
The amplifier's voltage gain into 8 ohms measured 28.5dB. The input impedance measured 98k ohms. The DC offset was a very low 1.1mV. The Premier Twelve is noninverting—a positive-going input emerges positive at the…
One of my favorite parts of attending Stereophile's Home Entertainment shows—aside from seeking out the sexy new gear and pressing the flesh of readers—is the "Ask the Editors" panel discussions. What begins as a Q&A session usually turns into a free-for-all, as the outspoken and opinionated likes of Sam Tellig, Michael Fremer, Ken Kessler, and John Marks barely give room for wallflowers such as Art Dudley and yours truly to express our opinions—except when editor John Atkinson asks each of us, in turn, to cast our votes for the "most interesting rooms to visit." At both the HE2004 and…
Sidebar 1: Specifications
Description: Two-way, reflex-loaded dynamic speaker with integral stand. Drive-unit: 4" cone unit with a neodymium magnet run full-range, 6.5" honeycomb-cone woofer with neodymium magnet. Frequency range: 45Hz–20kHz. Sensitivity: 90dB/2.83V/m. Nominal impedance: 6 ohms. Maximum power handling: 60W.
Dimensions: 15.6" (400mm) H by 7.8" (200mm) W by 13.25" (340mm) D. Weight: 19.8 lbs (9kg). Stand: 22.6" (580mm) H by 10.9" (280mm) W by 15.6" (400mm) D. Weight: 15.4 lbs (7kg).
Finishes: Black, matte or gloss.
Serial numbers of units reviewed: P220002/3.
…
Sidebar 2: Associated Equipment
Analog Sources: VPI TNT IV turntable, Immedia RPM tonearm, Koetsu Urushi cartridge; Rega Planar 3 turntable, Syrinx PU-3 tonearm, Clearaudio Virtuoso Wood, Aurum Beta S cartridges.
Digital Sources: Lector CDP-7T, California Audio Labs Icon Mk.II Power Boss, Creek CD53 Mk.II CD players; Pioneer DV-333 DVD player.
Preamplification: Vendetta Research SCP-2D phono stage, Audio Valve Eklipse line stage.
Power amplifier: Audio Research VT100 Mk.II.
Integrated amplifier: Creek 5350SE.
Cables: Interconnect: MIT MI-350 CVTwin Terminator, MI-330SG,…
Sidebar 3: Measurements
As Bob Reina explained, the Almarro M0A is deceptive-looking because what appears to be its stand is actually part of the speaker's acoustic design. I therefore measured it attached to the stand. I estimated the M0A's voltage sensitivity as 88.5dB(B)/2.83V/m. Though this is slightly below the specified 90dB, it is still higher than average. The M0A's impedance magnitude (fig.1) is quite different between the bass, where it averages 5 ohms, and the treble, where it rises from 6 ohms at 1kHz to more than 20 ohms above 12kHz. Using a tube amplifier with this speaker…
Musical arguments in favor of separate components are compelling and well-documented. But there's also something musical to be said about reducing the number of power sources, keeping signal paths short and direct, and hard-wiring connections between components rather than employing multiple sets of interconnects. So while a designer must inevitably confront certain tradeoffs, the explosive growth and popularity of single-box products in the past few years contradicts the received wisdom passed down by some of the more sniffy audiophiles: that such unduly proletarian products are terminally…