Every enthusiast, audiophile, and equipment reviewer has different criteria for selecting reference equipment. Some embrace gear based just on sound quality; others embrace gear on sound quality along with design philosophy. When it comes to amplification, I am admittedly a Class A guy, and I love the two Class A amplifiers I currently own: the 30-watt Pass Labs XA30.8 stereo amp and the 10-watt First Watt SIT-2 stereo amp. These amplifiers are deep-biasing, always ready to handle musical transients and dramatically shifting dynamics. Their downside is that they are inefficient and dissipate a lot of heat as they consume a lot of power. Nonetheless, these amplifiers are my references, matching like peas and carrots with my Focal Sopra No.1 speakers.
So, when Benchmark shipped me the AHB2 Reference Power Amplifier (100 watts per channel into eight ohms, 380 watts bridged mono into eight ohms) along with the new DAC3 preamplifier/DAC that I already reviewed, and I first read the manual--yes, I read manuals--I was initially taken aback. Terms like low-bias, Class H, Class G, and feed-forward error correction are not terms that accompany the workhorse amplifiers I usually live with. Benchmark clearly states that the AHB2 represents a "radical approach" to power amplification. Knowing the company's reputation and having owned its products in the past, I was definitely intrigued.
In my recent review of the DAC3, I discussed Benchmark's philosophy to pursue musical sonic transparency. Low noise and distortion are in the company's DNA and are the ultimate goals with every product produced. The AHB2 Reference power amplifier has a reported 132-dB signal-to-noise ratio. Now, while I never "get off" reading consumer product statistics because stats cannot ever replace actual listening tests, I must admit that my curiosity was further heightened. Could an amplifier with a reported signal-to-noise ratio greater than amplifiers produced by legendary designers like Coangelo, Curl, D'agostino, and Pass, and far greater than any recording (high resolution or otherwise), really be that much quieter? If so, does it matter?
The AHB2 is a handsome product that sells for $2,995, or roughly $1,000 more than the DAC3. It possesses a small footprint of approximately 11 inches by eight inches, and it is solidly built in the same brushed aluminum as the DAC3. The ABH2 is THX AAA Certified (utilizing several of the company's technologies/circuitries) and provides a plethora of additional features. These include, but are not limited to, fault protection security (which detects overloads, short circuits, clipping, excessive temperatures, and low input voltages and will shut the amplifier to protect it and your speakers), a two-way 12-volt trigger, an input sensitivity switch, auto shutoff, stereo and mono operation, XLR inputs, and NL4 speaker outputs. I connected the AHB2 to the DAC3 and utilized high-definition sources from my Synology 416 NAS server, as well as Red Book sources from TIDAL. All audio cables were from Wireworld, although I tried out the NL4 cables that Benchmark generously supplied.
I always try to listen to varied samplings of music--especially from high-resolution sources--which has recently become easier with TIDAL's "Master" recordings and my recent acquisition of a Mytek Brooklyn DAC (currently under review). I utilized the Benchmark DAC3 for all my listening, but I also tinkered with the Mytek Brooklyn DAC for some MQA listening.
While the AHB2 does not possess the liquidity of a fine tube power amplifier, I would describe it as masterfully (if not mercifully) detailed and transparent. Nothing in the music escapes the clutches of the AHB2. The smallest details on Steve Howe's acoustic guitars, such as the decay of each harmonic during the opening bars of "Chord of Life" or the clarity of his 12-string acoustic guitar on "The Preacher, The Teacher" from "And You and I" (Close to the Edge, MQA, 24/192), came through clearly. It improved my listening pleasure for a song that I have probably heard 500 times and is part of my favorite album of all time.
Furthermore, the tonality of the AHB2 is also absolutely spot-on. I recently scored a 24/192 DVD-Audio copy of Art Pepper Meets the Rhythm Section, and it is nothing short of a marvelous disc. It is so intoxicating that I cannot stop listening to it. Every song has a jazz nightclub feel, and I would put it up against any jazz record from any era in terms of sound quality. Throughout the album, drums played by Philly Joe Jones had such striking realism that even my wife, a casual listener, made an unsolicited remark on how lifelike they sounded. The tonal balance of Art Pepper's saxophone and Red Garland's piano were nearly without flaw. Well played.
Listening to track after track on Audioslave's flip disc (Audioslave, 24/48) proved that the AHB2 also packs serious punch. This album is a fine recording and contains serious dynamics and transients (listen to "Exploder"), all of which the AHB2 handled with ease. As with a Class A amplifier, I could detect the muscle of the AHB2 and hear it in the sheer weight of presentation in the lower octaves. Bass was taught, deep, and fast even for my bookshelf Focal Sopra No.1 speakers, which begin to roll off at about 50 to 60 Hz. While many hard rock albums have a tendency to sound harsh or muddy, none of those traits were apparent here through the Benchmark AHB2.
• The AHB2 has a small footprint, runs cool, consumes little power (especially in standby mode), and is environmentally friendly.
• The AHB2 can drive virtually any speaker load with significant power--especially in monaural mode--yet it never lacked finesse on delicate passages.
• The AHB2 is sonically transparent, images beautifully, and authoritatively delivers tons of bottom end, which is likely a factor of it being so quiet.
• The AHB2 resolves detail with merciless precision. This is a strength in my view, unless you get easily distracted by hearing unwanted details in the source like hum, clipping, or poor editing--in which case the AHB2 may not be your cup of tea.
• The AHB2 accepts unbalanced sources but only with a Benchmark-supplied unbalanced RCA adapter. Benchmark claims that high-level balanced sources are required to effectuate low-noise systems and thus connection to RCA sources is not recommended.
Comparison and Competition
There are too many two-channel, solid-state stereo amplifiers in the $3,000 price range to name anywhere close to an exhaustive list. Names that come to mind include the Red Dragon S500 ($1,900), Rotel RB-1590 ($2,999), and NAD M22 ($2,999), as well as more expensive offerings like the McIntosh MC152 ($4,500) and even the Arcam FMJ P49 ($4,999). In my view, the Benchmark AHB2 can compete with any of them.
The Benchmark AHB2 embodies everything that a solid-state amp should. It is a technologically advanced and remarkable amplifier that can hang with any amp in its class because it is sonically transparent, images beautifully, and produces authoritative bass. While costing only $2,995, it is hard to imagine asking for much more in a power amplifier. In fact, if the AHB2 cost another $1,000, I would still call it a bargain. Interestingly, while my Focal speakers are easy to drive, the AHB2 can probably drive a set of modestly inefficient floor-standing speakers to reasonable listening levels without any strain whatsoever. If you are looking to spend between $2,500 and $4,500 on a stereo, solid-state amplifier, it would be foolish not to consider the AHB2 a strong contender.
• Check out our Stereo Amplifiers category page to read similar reviews.
• Benchmark DAC3 HGC DAC Reviewed at HomeTheaterReview.com.
• Visit the Benchmark Media website for more product information.