Reviews

"For years, the audio world acknowledged one main contender (at least at sub-five-figure pricing) for the quietest, cleanest, most neutral power amplifier around. That was the Benchmark AHB2, whose specifications are still, for all practical purposes, unsurpassed, even by today’s excellent Class-D amps."

"10 years after its release, the Benchmark Media Systems AHB2 stereo power amp is still a standard-bearer in clean, neutral sound in the audiophile world."

"I greatly enjoyed having a pair of AHB2s in my system – their purity, neutrality, and seemingly unlimited power provided a clear window on the music and a lot of joy."

"I especially appreciated the AHB2’s smooth, well-integrated treble, free of splashiness or grain, and its natural reproduction of the human voice."

- Mike Prager, Future Audiophile

"The AHB2 bridgeable stereo amplifier ... was the topic of a recent discussion between American electrostatic panel speaker manufacturer Sound Lab’s president, Dr. Roger West, and me."

"In our discussion, he related his highly positive experience in driving even his largest, $55k Majestic 945 panels with the $7,000 pair of Benchmark Media AHB2 monoblocks, along with the $3,050 LA4 Preamplifier and factory XLR cables."

"Dr. West described the AHB2 as a class AB design using “feed-forward distortion reduction [thus removing] any possibility of pushing the margin of safety of a standard feedback loop, used in most amplifiers, into an unstable oscillatory mode.”"

"He further shared with me that “this is of most concern on powerful musical transients. The distortion of the amplifier in the balanced mode is astonishingly low even at just below the clipping level of 380 watts.”"

"The prospect of the AHB2’s specified distortion level of 0.00015% or lower when at full volume is comical at first glance, but upon actual audition the impact of the achievement is very audible from medium-high listening levels and upward."

"It was unlike any other sub-$20,000 amplifier I have auditioned."

"My audition of the Benchmark Media AHB2 amplifiers underscores the reason Dr. West is so taken by it, and confirms the design is best described as a watershed moment in the high-end audio industry."

- Constantine Soo, Dagogo

"I began with the DAC3 HGC and AHB2 powering the glorious Morel Avyra 633 three-way floorstanders."

"This pairing created a full-bodied sound which brought the recording to life."

"Notable from the off was the bass from the DAC3 HGC and AHB2."

"Wow! It was deep, tight and conveyed a real feeling that the electronics were in charge of the transducers."

"Involuntary foot-tapping confirmed the timing ability and the overall presentation was spot-on, the Benchmark electronics created a fluent sound across a vivid soundstage; performers evident both tonally and spatially in an easy-to-believe presentation that brought the performance close."

"The Benchmark’s ability to retrieve deep-down detail and display it so well across the soundstage, with accurate positioning and convincing layering, made for a glorious re-creation of the recordings."

"To my mind the AHB2 is an amplifier with no obvious characteristics of its own: the level of transparency is sublime."

"Above all, the improved transient response performance stood out in a presentation that was not only lively but incredibly fast and revealing. The attack and decay displayed was awesome and not something I expect at this price point."

"The Benchmark DAC3 HGC and AHB2 are cracking products, sonically superior to a lot that’s available and well priced."

"They are superbly designed and built to an extremely high standard."

- Trevor Butler, the-ear.net

"The Sound of Silence"

"Benchmark Audio is an engineering focused company with a deep heritage in the recording studio world."

"The HPA4 is a Headphone Amplifier and Preamp that incorporates the THX-888(AAA) achromatic audio amplifier circuit that was first introduced to the world in the Benchmark AHB2 amplifier."

"To this day the AHB2 remains the lowest distortion and highest SNR amplifier on the market."

"The Direct Opposite of Typical Tube-Based Technology"

"From a listening stance it is the cleanest and most accurate delivery of sound you are likely to get with any Hi-Fi component."

"This is the direct opposite of the typical sound of tube-based technology that is awash in second harmonic distortion and noise."

Power

"The HPA4 …offers 6 watts into 16 ohm and a whopping 11.5 Vrms into 300 Ohm headphones."

"You will not be running out of power with this device."

Listening

I used the track "Slink" from the brand-new Artemis album on Blue Note."

"It is a very dynamic driving track and the Artemis ensemble makes the most of it. The HPA4 and revealed all the sonic details of this track."

"I give the HPA4 my highest recommendation."

- Chris, Forum Administrator - DC Hi-Fi Group

AHB2 - Receives Stereophile's Highest "A" Rating for Power Amplifiers

"Benchmark's 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."

- Stereophile, 2023

"Much more apparent low-level detail in already-familiar recordings" - Kalman Rubinson

"A tonal balance that sounded more 'right' than any of [the other amps on hand]." - Kalman Rubinson

"An extraordinary amplifier." - John Atkinson

Why Did You Buy Benchmark Gear?

"I'm asking because clearly Benchmark is a highly regarded company here, and plenty of ASR members own Benchmark amplification/DACs."

"We know they are top of the heap in terms of measured performance, outdoing plenty of the competition in terms of typical distortion measurements."

- @MattHooper, Forum Member

Some of the Replies:

"I bought the AHB2s because I liked the sound from the get-go and the excellent measured performance was a great confirmation. I also like the size/weight."

- @Kal Rubinson, Forum Member, Stereophile Reviewer

"Been using Benchmark since the DAC1 came out."

"So far the only thing to displace a Benchmark product has been newer upgraded Benchmark products."

- @SoundGuy, Forum Member, AudioScienceReview.com

"AHB2, LA4, DAC3 ... Would I do it all again? Absolutely."

- @KellenVancouver, Forum Member

Comments from Amir's AHB2 Test Report:

"The Benchmark AHB2 breaks new ground with respect to performance of power amplifiers."

"The Benchmark AHB2 gets my strongest recommendation."

- Amir Majidimehr (@amirm), Forum Founder/Admin

DAC3, AHB2 - Driving Note Line Array

"The afternoon before the start of the show I ran into John Siau of Benchmark Media Systems. He says to me quietly, “make sure you stop in our room, we have a surprise!” With curiosity suitably piqued, Co-Editor Jim Clements and I paid a visit ..."

"The results were pretty astonishing. A stable, enveloping stereo image that was devoid of any distortion whatsoever."

- Carlo Lo Raso, Secrets of Home Theater and High Fidelity

DAC3 B and AHB2 - Driving Laufer Teknik Note Line Array

Two AHB2 bridged-mono amplifiers were driving the 4-Ohm line arrays (48 drivers per side).

"Sound was extremely well-integrated and controlled, and the bass memorable."

"The Note received signal through Benchmark Media's AHB2 power amps, DAC3 B D/A processor, and interconnects."

Two DAC3 B Converters - One for the Array, and One for the Subs

Two AHB2 Power Amplifiers - Bridged Mono Mode - One per Array

"The system sounded super on a 16/44.1 file of the famed rendition of Copland's Fanfare for the Common Man, recorded by Eiji Oue and the Minnesota Orchestra for Reference Recordings."

- Jason Victor Serinus, Stereophile Magazine

DAC3 B, AHB2, Note Line Array - "Most Immersive Listening Experience"

"The most immersive listening experience I had the entire show."

"There is no sweet spot because everywhere is the sweet spot. Even behind the speakers sounded incredible!"

"SVS Subs doing the low end work and Benchmark 380 watt class H monoblocked amps driving the arrays."

"I spent an extended amount of time in this room."

- LongLiveAnalog, r/audiophile on Reddit

AHB2 - Stereo Times "Most Wanted" Award

"Merriam-Webster defines a benchmark as "something that serves as a standard by which others may be measured or judged." This is what the AHB2s has become for me."

"A pair of AHB2s are now part of my dedicated summertime amplification for my Sound Lab 545PX loudspeakers."

- Don Shaulis, The Stereo Times

AHB2 - "Found a Home in My System"

"I was led to Benchmark Media Systems through recommendations from Roger West, the designer of Sound Lab speakers. Praise from a local Sound Lab dealer and a local Sound Lab owner effectively twisted my arm to the point where I yielded to temptation to try the amplifiers ..."

"The Class-H Benchmarks give me what I wanted from Class-D amplifiers, but with the musical engagement, I found lacking in Class-D. There is the added benefit of a company that has been in business for over 36 years and has a depth of products, and offers an extended warranty."

"The highest compliment I can pay a piece of audio equipment is that it has found a home in my system. A pair of AHB2s are now part of my dedicated summertime amplification for my Sound Lab 545PX loudspeakers."

"The Benchmark performance continues to engage me, and the company gives me confidence in long-term support."

- Don Shaulis, Stereo Times

AHB2 - "I love, I love, I love my Benchmark Power Amps!"

- Theo Nicolakis, Audioholics Online A/V Magazine

Theo uses a pair of AHB2 power amps in bridged mono (480 W into 6 Ohms) to drive a pair of Revel Ultima Salon2 loudspeakers ($20,000/pair). This is his reference amplifier-speaker combination.

Watch the video to find out why he loves his AHB2 amplifiers:

DAC2, HPA4, AHB2 - "The Benchmark Hi-Fi Stack ..."

"Find a Better Hi-Fi Stack! Double-Dog-Dare you!"

- Ron, NewRecordDay.com

AHB2 - "Reveals All"

Jay discusses the sonic tradeoffs between transparency and the sound of tube-induced distortion. He describes how his tube amps may make poor recordings sound enjoyable while the AHB2 reveals all.

AHB2 - "I Purchased Two Units With My Hard-Earned Money"

"The highest compliment I can give to AHB2 is that I purchased not one, but two units with my hard-earned money. These weren’t loaner units and this wasn’t a sponsored review and you can draw your own conclusions."

"The AHB2 might look small and lightweight, but thanks to its clever engineering and power supply implementation, this little fellow could still deliver 190 Watts in 4 Ohms and 100 Watts in 8 Ohms, while maintaining an undetectable noise floor and distortion."

"For the craziest folks out there, you can even bridge two pieces together for ~580 Watts in 4 Ohms and 380W in 8 ohms."

- Sandu Vitalie, SoundNews.net

"The Benchmark AHB2 is a power amp meant to power speakers. There seems to be an interest in it for hard to power headphone enthusiasts on the forum even though Benchmark makes the HPA4 which is a headphone amp. That said, folks trying to drive the Hifiman HE-6 and Susvara gravitates towards this piece of gear."

"Finally, I pulled the trigger on the AHB2 and couldn’t be happier."

 "None of these have been provided to me. I bought everything pictured."

AHB2 - As a Headphone Amplifier - "My Daily Driver V2.0"

Hifiman Susvara Headphones - Driven by Benchmark AHB2

"Holy mother of Thor, this is dynamics, speed, transient response, resolution and transparency incarnate into a single metal box. There isn’t a clearer, a more resolving or a more transparent sounding amplifier out there, this is a wire with gain amplifier that doesn’t add anything into the mix."

"You can’t get a more impactful, a faster or cleaner sounding amplifier.

- Sandu Vitalie, SoundNews.net

AHB2 Headphone Adapter Cable

AHB2 - Mono Mode - "The Playback in Mono Mode is Off the Charts"

"The HPA4 and AHB2 have been a fixture in our reference set for several years now."

"In stereo mode we get a nice 100 watts (8 ohms class A/B) but in mono that goes to an impressive 380 watts!"

"We set the small switch on the back of the AHB2s to mono and connect each speaker to an AHB2."

"The playback in mono is 'off the charts' ... there's no going back really. You have been warned!"

"Benchmark Media Systems Inc from Syracuse, New-York is an American company and has been one of the top pro-audio manufacturers for thirty years. In recent years they have also ventured into the consumer market with considerable success."

"In collaboration with THX came the AHB2 power amplifier and not much later they developed a suitable headphone amplifier and preamplifier, the HPA4 and LA4 respectively."

- Geoffrey Vanhouwaert, Alpha-Audio

AHB2 - "A-Rated Power Amplifier"

The "A" rating is the highest honor awarded in the Power Amplifier category.

"Benchmark's 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."

"Much more apparent low-level detail in already-familiar recordings" - Kalman Rubinson

"A tonal balance that sounded more 'right' than any of [the other amps on hand]." - Kalman Rubinson

"An extraordinary amplifier." - John Atkinson

AHB2 - "Thumbs Firmly Aloft"

Stereonet Applause Award - Benchmark AHB2

"I can't think of many amps with dual hi-fi and pro functionality. Maybe Bryston and the odd ATC, but there aren't a lot. However, to this shortlist, we can add Benchmark."

"Two things strike you upon first seeing it – it's surprisingly compact, and it also has the sort of features that make it more at home in a studio than a listening room lounge space."

"You can bridge the AHB2 to make it a monoblock, or bi-wire it to a single speaker; there are only balanced connections incoming, as well as a choice of gain to match the speaker. You get normal speaker binding posts plus a pair of Neutrik's SpeakOn connectors on the output side."

"Thumbs firmly aloft then for this compact, versatile, thoughtfully designed, well-built stereo power amplifier."

- Rafael Todes, Stereonet.com