"This THX-888 amplifier is driven by a Benchmark line amplifier that features relay gain control, relay input selection and relay muting. The gain control has a whopping 256 steps in impressive 0.5 dB increments so that you can get exactly the volume that you want to hear!"
"You get a brilliant Touch Screen that in the end provides easy access to the plethora of features and settings on the amplifier. Everything from balance control, input level offset selection, personalized input names, screen dimming, remote control and function-locking are only a touch or two away with the intuitive user interface. Throw in an optional remote control, and you really get everything you’d ever need with a dedicated headphone amplifier."
"The HPA4 is 100% analog and is driven by an upstream D/A converter (DAC). The THX-888 can easily deliver high voltage into low-sensitivity high impedance headphones and it can conversely deliver high current into low impedance headphones. It easily drove all of the headphones I had on hand from my 300 ohm Sennheiser HD800S, to my 32 ohm Grado PS2000e and power hungry Abyss AB-1266 Phi TC orthomagnetic headphones. Heck, it was also dead silent on lower gain with all of my in-ear monitors too like the Grade GR10e IEMs. It literally is both a jack of all trades and master of all!"
"I plugged in the HD800S headphones and quickly selected Holly Cole’s “Collection Vol. 1”. This collection of classic Holly Cole songs is one of my favorite “go to” albums."
"The tonality of the piano in “Trust in Me” was simply “life-like”. The tonality and detail of Holly’s piano playing was as if I was transported to a jazz club with Holly paying in front of me. Her vocals were seductive, transparent and perfectly portrayed. The HPA4 amplifier offered an incredibly close look into this recording with the ability to mine out the smallest details that other amplifiers would seem to gloss over."
"Since the HPA4 arrived, I have rediscovered so many of my favorite works all over again with improved detail retrieval dynamics and transparency that it’s hard to pull myself away!"
"It drove my power hungry Abyss Phi TC headphones with complete authority, but it was still dead silent and nimble enough to amplify my easy to drive Focal Utopia headphones."
"Rarely have I come across such a wonderfully revealing amplifier that can drive many different types of headphones so darn well! The solid build construction and various controls make the $2,995 price tag seem a bit low based on the other headphone amplifiers in this market space."
- Peter Pialis, Headphone.guru
November 6, 2019
"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
"Benchmark's LA4 is the widest-bandwidth, widest-dynamic-range, lowest-noise, lowest-distortion preamplifier I have encountered."
- John Atkinson, Stereophile
"The LA4 is probably the most transparent and revealing audio component I've ever used. It does not seem to leave any fingerprints on the sound."
- Kalman Rubinson, Stereophile
"Class A" is Stereophile's highest award for preamplifiers.