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In my four years of doing equipment reviews for Stereophile, I've had in my listening room, for varying periods, tube amplifiers from Audio Research, Sonic Frontiers, Luxman, VTL, Cary, Audion, Conrad-Johnson, and Quicksilver. Some had the "magic" (tubeophiles will know what I mean) but were deficient in other ways: insufficient power to drive most speakers to realistic levels, weaknesses at the frequency extremes, etc. Others had lots of power and wideband frequency response, but were missing the magic.

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To get a handle on the YBA 1 Alpha HC's performance in comparative terms, I spent a lot of time switching back and forth between it and the Jeff Rowland Design Group Model 2. In many ways, these amps are natural peers/competitors. They have similar power ratings (Rowland, 75Wpc; YBA, 85Wpc); they're in roughly the same price range (Rowland, $5800; YBA, $7000); they're both small but heavy; and both represent their designers' at-times-fanatical pursuit of the twin goals of accuracy and musicality. The Rowland Model 2 is firmly…

Like many audiophiles, I've been impressed with the effectiveness of dedicated AC lines and line conditioners. Although power supplies in audio equipment are supposed to provide isolation from the various sorts of interference (EMI and RFI) that may be present on AC, cleaner AC power usually translates to cleaner sound. If reducing EMI/RFI from the power source is worthwhile, it follows that eliminating it should be even better (footnote 1). This is the promise of battery power: by having a source of pure DC, you are, in…

Analog Source: Fully updated Linn LP12 turntable, Ittok tonearm, AudioQuest AQ-7000nsx cartridge.
Digital Sources: PS Audio Lambda II and Sonic Frontiers SFT-1 transports, Audio Alchemy DTI•Pro32, Sonic Frontiers SFD-2 Mk.II digital processor, Illuminati D-60/Orchid digital links; Sonic Frontiers SFCD-1 CD player.
Preamplifiers: Convergent Audio Technology SL-1 Mk.II, Balanced Audio Technology VK-5i, Jeff Rowland Design Group Synergy.
Loudspeakers: Dunlavy Audio Laboratories SC-IV, Vienna Acoustics Mozart.
Interconnects, speaker cables, power…

All measurements on the Rowland Model 2 were made with the amplifier in its high-impedance input setting at a gain of 26dB, unless otherwise noted. All of the measurements were, of course, balanced. And all of the measurements, again except as noted, were made with the battery functioning normally (battery connected to the line for constant recharge, amp operating off the battery).

Following its 1/3-power, one-hour preconditioning test, the Model 2's heatsinks were very warm but not hot. The Rowland Model 2's input impedance measured 44k ohms (720…

Description: Solid-state stereo power amplifier. Power output: 75W into 8 ohms (18.75dBW), 150W into 4 ohms (18.75dBW). Power bandwidth: 0.5Hz-160kHz -3dB. THD+noise: <0.05% at rated power. Damping factor: >100, 20Hz-20kHz, 8 ohms, equivalent to an output impedance of less than 0.08 ohms. Output current: 20A continuous, 35A peak. Overall gain and sensitivity: 26dB or 32dB; 141mV or 72mV (1W, 8 ohms). Input impedance: 36k ohms or 600 ohms. Common-mode rejection ratio: >60dB, 20Hz-20kHz. Power consumption: 25W standby; 225W idle; 400W maximum.
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First of all, while a 200W amplifier is 8dB more powerful than one rated at 30W, that 8dB sounds only about twice as loud to the human ear, not the seven times you'd expect. For an amplifier to play music…

All external connectors are located on a cramped panel at the rear, between two heatsink fins. This maximizes the…

What listening indeed
The Aleph 3 takes at least an hour to warm up to its final operating state. Both measured distortion and noise are higher when it is cold. Still, the amp…

To cut to the chase, the Aleph 3 sounded better. There was a definite family resemblance between the two—that friendly coherence that all good single-ended amps seem to convey—but the…