AHB2 - "This stable and load-independent behavior ... is something not often encountered"
"This stable and load-independent behavior of the output stage is something not often encountered and adds, of course, another positive point for the device."
"AHB2's output power, near its clipping limit, was measured at 108Wrms per channel into 8 Ohm loads and at 190Wrms per channel at 4 Ohm loads, easily confirming the specs given by the company itself."
"Based on this performance, the amplifier seems more than capable of driving difficult loads."
"Damping factor was estimated above 200, therefore, no system frequency response discrepancies, due to loudspeaker's impedance variability, should be expected."
"In distortion measurements, AHB2's behavior was impressive with a total harmonic distortion and noise (THD+N) figure at 0.0009% for 8 Ohm loads and 0.0012% for 4 Ohm loads (measured at 1/3 of its maximum power) and harmonic distortion at 0.0005% and 0.0009% for 8 and 4 Ohm loads respectively."
"Intermodulation distortion (SMPTE) was also low, at 0.0005% and 0.0007% (8/4 Ohm loads). This performance clearly shows that the Benchmark/THX design approach works in practice as intended (at least from the distortion point of view) and the result is a power stage with very low distortion, indeed."
"The frequency response of the amplifier (with an 8 Ohm load) was practically flat with a slight attenuation towards the high-frequency part of the spectrum which is very progressive and does not exceed 0.3dBr at 60kHz."
"The noise performance of the amplifier was, also, top-class. With a reference level corresponding to 1Wmrs/8 Ohm, the signal to noise ratio was measured at -109dBr (A) (with a 1kHz input signal) and the dynamic range at 129dB."
"In both spectrum graphs, there is an apparent absence of noise components from the power supply and their intermodulation products in the low-frequency range (the 50Hz component is hardly distinguishable), all of them being below -130dBr. This is a remarkable behavior, especially with the output stage under load conditions, which justifies the choice of a switch-mode power supply."
"Finally, the square wave response shows a very good transient behavior, without any particular problem. Slew rate was estimated at 16V/uS and rise time at 3.5mS, a value that corresponds to a conventionally calculated bandwidth of 100kHz."
- Dimitris Stamatakos, AVMENTOR.net
"This contest produced another tie, and yet another contrast between two wildly different philosophies—economical, if not technical. As Jim Austin pointed out in his initial review, the DAC3 HGC D/A processor from Benchmark Media Systems—a company known for making pro-audio as well as domestic-audio gear—sells for less than the price of certain high-end interconnects. The dCS Vivaldi D/A processor sells for 16 times the Benchmark's price, and in our pages was first reviewed, by Michael Fremer, as part of a $114,996 dCS digital front end."
"Both DACs impressed their respective reviewers with magnificent sound—and in his measurements for both, John Atkinson offered the same one-word conclusion: "Wow!""
"In my September 2018 column, I wrote of my discovery of miniDSP's U-DIO8, which converts multichannel data fed to its USB port to eight S/PDIF or AES-EBU outputs at resolutions of up to 24-bit/192kHz. Armed with a U-DIO8, you can use three or four of your choice of stereo DAC."
"I went commando with the DAC3s directly connected to the three AHB2s. All three DAC3s were set to Home Theater Bypass, and I used JRiver Media Center's volume control."
"For the first time I can recall, I heard no noise from my system, even with an ear flush against a tweeter."
"I know that we audiophiles can obsess about small changes and make them seem more important than they actually are, but that's what this hobby is about: Eliminating as many audible flaws as possible, however tiny. In this case, the effect was striking at first listen, and endured through everything I played, even tracks that had troubled me before."
- Kal Rubinson, Stereophile
"RMAF 2018 was really good, with significant numbers of attendees, and more new-product introductions than I remembered ever seeing there."
"Led by engineer John Siau and based in Syracuse, New York, Benchmark Media Systems has built a sterling reputation for making compact, well-engineered, moderately priced electronics that challenge the state of the art, both on the test bench and in the listening room."
"What I took notice of were the specifications: total harmonic distortion of less than 0.00006%, and a signal/noise ratio exceeding 135dB from 20Hz to 20kHz."
"If those claims are true, and there’s no reason to believe they aren’t -- Benchmark gear has always performed as specified on the test bench -- the LA4 should be about as transparent-sounding a line-stage as you can find at any price."
- Doug Schneider, SoundStage! Hi-Fi