Overview

The Benchmark AHB2 is a Class-H power amplifier featuring THX AAA (Achromatic Audio Amplifier) technology developed by the company. Since its 2016 release, it has recorded SINAD 113dB on Audio Science Review, achieving world-class transparency in measurements. With 100W into 8Ω and 190W into 4Ω output, it employs a feedforward error correction system to eliminate distortion to the extreme limits.

Scientific Validity

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The measured values of THD+N 0.00013% (at full power), SINAD 113 dB [1], and S/N ratio 132 dB A-weighted represent world-class levels that significantly exceed transparent thresholds. Frequency response of 0.1 Hz–200 kHz +0/-3 dB and crosstalk below -115 dB meet transparent criteria across all indicators. Audio Science Review rated it as “the best we have tested” [1], and Stereophile measurements recorded 0.0005% THD+N (33 W, 8 Ω) [2]. With distortion levels far below auditory thresholds, it provides scientifically meaningful sound quality improvements.

Technology Level

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THX AAA technology with feedforward error correction and Class-H operation represents industry-leading design. The bipolar output stage and proprietary power efficiency optimization achieve low distortion characteristics difficult to attain with conventional Class-AB or Class-D designs. Peak output current capability up to 29 A and damping factor (350 at 20 Hz, 254 at 1 kHz, 34 at 20 kHz) demonstrate advanced circuit design achievements. However, it remains within conventional analog amplification technology and cannot be considered revolutionary new technology.

Cost-Performance

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Street price is 3,499 USD (B&H) [3]. As the cheapest transparent alternative with equal or better functionality/performance, a Purifi 1ET400A stereo power amplifier (e.g., Buckeye Amps 1ET400A 2ch at 1,499 USD) delivers ≥200 W into 8 Ω-class power with state-of-the-art low distortion. Therefore:

1,499 USD ÷ 3,499 USD = 0.428… → rounded to 0.4

Because cheaper fully transparent options exist, the cost-performance of AHB2 is limited.

Reliability & Support

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Provides 5-year warranty and established service structure in North America. Benchmark Media Systems has over 20 years of track record as a professional audio manufacturer with stable product quality. However, domestic support structure in international markets is limited, potentially requiring extended response times for failures. Firmware updates do not apply to this analog product.

Rationality of Design Philosophy

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The scientific approach thoroughly pursuing measurable distortion elimination is rational. Objective performance improvements through THX AAA technology are commendable, but with Class-D amplifiers already achieving sufficient transparency at low cost, investment significance in expensive analog circuits is limited. The existence significance as dedicated audio equipment is questionable when equivalent functionality can be realized with general-purpose equipment (PC + Class-D amplifier) at 1/10 the cost.

Advice

Recommended primarily for measurement-focused users without strict budget constraints. As practical alternatives, Purifi 1ET400A-based stereo amplifiers (e.g., Buckeye 1ET400A 2ch at 1,499 USD) deliver equivalent or better transparency and ample power at much lower cost. If allocating 3,499 USD toward sound quality, improvements to speakers or room acoustics often yield larger audible gains. Unless brand status or “ultimate measurement” satisfaction is a priority, consider the cheaper transparent options.

References

[1] Audio Science Review, Benchmark AHB2 Review (Updated Measurements), https://www.audiosciencereview.com/forum/index.php?threads/benchmark-ahb2-review-updated-measurements.50844/, Accessed: August 2025, SINAD: 113 dB

[2] Stereophile, Benchmark Media Systems AHB2 power amplifier Measurements, https://www.stereophile.com/content/benchmark-media-systems-ahb2-power-amplifier-measurements, Accessed: August 2025, THD+N: 0.0005% at 33 W/8 Ω

[3] B&H, Benchmark AHB2 High-Resolution Power Amplifier, https://www.bhphotovideo.com/c/product/1010349-REG/benchmark_ahb2_high_resolution_power_amplifier.html, Accessed: August 2025, 3,499 USD

(2025.8.9)