"The AHB2 makes use of THX Corporation's Achromatic Audio Amplifier (AAA) technology, in which a low-power feed-forward amplifier drives a low-bias class-AB output section, the latter energized by a system of class-H power-supply rails that deliver power in response to demand - resulting in an extremely efficient amplifier capable of robust power output."
"More apparent low-level detail" - KR
"In his listening tests, Kalman Rubinson discovered 'much more apparent low-level detail in already-familiar recordings' - a characteristic he credited to the Benchmark's evident noiselessness - and a tonal balance that 'sounded more right' than any of the other amps on hand."
"An extraordinary amplifier" - JA
In measuring the AHB2 and attempting to confirm its specified very high signal/noise ratio, John Atkinson observed nonlinearities in his testing equipment that 'Haven't affected the measured performance of other amplifiers I've tested, but they were detectable with the AHB2's very low intrinsic distortion and noise.' His conclusion: 'an extraordinary amplifier.'"
"Kalman Rubinson's last word: 'bargain'"
- Stereophile 2016 Recommended Components, April 2016
Read the Stereophile Bench-Test Report →
Stereophile rates recommended components by placing them in one of 6 classes; A, B, C, D, E, and K. Of these, the highest rating is "Class A". Benchmark shares this small and elite class with amplifiers costing 10 to 20 times more than the AHB2.
"Best attainable sound for a component of is kind, almost without practical considerations; 'the least musical compromise.' A Class A system is one for which you don't have to make a leap of faith to believe that you're hearing the real thing."
"Before I dig into the sound of the LA4 it is important to know that it employs a wide bandwidth design. The LA4’s bandwidth is specified at 0.2 Hz to 500 kHz."
"Most of the wide bandwidth designs I have heard exhibit ... a purity in tone with superb timing and speed ... the LA4 proved to be no exception."
"The Benchmark LA4 yielded a change that was quickly apparent in several areas. Notably were; bass, upper midrange, treble, low-level listening, and the ability to distinguish the colorations of other components that were contributing to my overall sound."
"Acoustic guitar, piano, and harmonica among many other instruments are presented with speed, clarity, and coherency that made them sound more “present” in the room and less like a recording."
"The Benchmark LA4 is simply the most transparent, least colored, and most revealing component I have had in my system to date. I look forward to it joining my stable of reference components."
"Highly recommended."
- Ken Redmond, The Audio Beatnik
"This little unit will change the way you look and listen to amplifiers."
"My first taste of this remarkable new amplifier came earlier this year in April at Chicago's AXPONA where I discovered it driving a newly redesigned Studio Electric Pasadena loudspeaker, also bearing the Benchmark trademark. Now called the SMS1, the Pasadena's crossover had been reworked by Benchmark, upgraded with very low tolerance components, and the new look, more in line with the look of the rest of the Benchmark product line up, had been adopted."
"The subsequent sound in this room was one of the most musically engaging I encountered at this year's event, a remarkable result considering its modest overall system price of just over $7000, sans source."
- Greg Weaver, EnjoythMusic.com
Jim Austin wrote, "The DAC3 was all about depths, in several respects . . . I heard deeper into the music."
The concise conclusion to John Atkinson's Measurements sidebar: "All I can say is 'Wow!'"
In a Follow-Up, Jim Austin wrote of using the Benchmark processor with the same company's AHB2 power amp—a combination of high source output voltage and modest amplifier gain that he describes as "optimal for minimizing noise and distortion"—and reported hearing "richer and more interesting" reproduction of very subtle details.
- Stereophile Magazine
"Class A+" is Stereophile's highest award for Digital Processors
