In 1983, in a garage in Garland, Texas, Allen Burdick began building high-performance audio equipment for television under the name Benchmark Sound Company. Two years later he incorporated the company as Benchmark Media Systems, relocated to his home town of Syracuse, New York, and expanded into other market segments, including professional and home audio. Benchmark’s hardware is designed for professional applications and continuous operation 24/7, which makes it perfectly suited to less demanding home use. Benchmark’s current product line includes the DAC3 family of digital-to-analog converters, the AHB2 stereo power amplifier, the HPA4 headphone amp and LA4 line preamp, and a variety of interconnects, digital links, and speaker cables. Most Benchmark components can be purchased with rack-mount faceplates for professional use, or with standard faceplates.
Recently, a brown-shirted man driving a brown-painted truck bestowed on me a new preamplifier, one of two currently available from Benchmark and the subject of this review: the LA4 line stage ($2499; all prices USD). At $500 more, the HPA4 adds the well-regarded THX-888 Achromatic Audio Amplifier (AAA) headphone circuit. Each model can be ordered through Benchmark’s website with a black or silver finish; add $100 for Benchmark’s standard-issue, all-metal remote control, and $200 for a full-width, rack-mount faceplate. Like all Benchmark products, the LA4 is designed and assembled in the US, from which most of its major components are sourced.
The LA4 arrived double-boxed and in pristine condition. Like most Benchmark gear, it’s small: at 8.65”W x 3.88”H x 8.33”D, or about half the width of a standard pro-audio component, it’s slightly narrower and about twice as tall as my reference DAC, Benchmark’s own DAC2 HGC. I’m enjoying the current trend of ever-smaller audio components producing ever-better sound, and stacked up, the LA4 and DAC2 HGC look nice. The LA4 weighs only 8 pounds, but felt totally solid in my hands. My review sample had a black case with a thick silver faceplate and black mounting bolts and feet -- all part of Benchmark’s no-nonsense design style. The case feels more upscale than my DAC2 HGC’s utilitarian, pedestrian-looking housing of folded sheet metal: the LA4’s side panels are as thick as its faceplate, with nicely radiused edges. Benchmark includes extra fuses and a power cord; my sample came with the $100 remote-control option -- the same remote that came with my DAC2 HGC.
The left half of the LA4’s front panel is dominated by a 3.5”, full-color, capacitive touchscreen; below it are a small power button and tiny IR sensor. The right side is mostly devoted to an engraved Benchmark logo and a good-size volume knob. That’s it. The touchscreen menu lets you adjust all of the LA4’s functions and features, including screen brightness, balance, and soft (-20dB) and full mute. The volume level is displayed numerically in dB, and as a large bar graph easily visible from across the room. Additional menus let you enable or disable each input and set its name and volume level, set up the auto power/trigger and remote control, reset the system, and lock all settings (similar to a child safety lock). Operation of the user interface is intuitive -- I found the LA4’s many features easy to find and adjust.
On the LA4’s rear panel are four pairs of analog inputs -- two balanced (XLR) and two unbalanced (RCA) -- two 12V trigger ports, one pair each of balanced (XLR) and unbalanced (RCA) outputs, a mono output (XLR), a fuse bay, and an IEC power inlet (100-240V, 50/60Hz). All connections and ports felt solid and sturdy.
Benchmark is respected for its hardcore engineering -- their top priority is exceptional measured performance. The LA4 was designed from the ground up as an ultra-low-noise, ultra-low-distortion mate for the AHB2 power amplifier, which my brother Hans reviewed on SoundStage! Access in June 2015. Our measurements of the AHB2 confirmed that it had the lowest noise and distortion of any power amp we’ve ever measured. Benchmark claims that the LA4 (and HPA4) “may be the only preamplifiers or line amplifiers that [exceed] the signal-to-noise ratio of the ultra-quiet AHB2.” If so, the LA4 may be closer to the elusive ideal of a “straight wire with gain” than almost any other preamplifier on the market at any price.
The LA4’s relay-managed volume control has 256 steps of adjustment of 0.5dB each, and is fully balanced -- each channel has its own dedicated attenuator. Each increment of volume adjustment produces a satisfying click from the 40 relays inside. Other circuit features include precision-timed relay closures, gold contact points in the relays, and metal-film resistors.
The LA4 has an expansive specified frequency response of 0.1Hz-500kHz, -3dB. Other impressive specs include a signal/noise ratio of >137dB (A-weighted) and total harmonic distortion (THD) of <-125dB (<0.00006%). Benchmark has also tested the LA4 for “immunity to radiated and conducted radio frequency interference.” The power draw is modest: an average of 12W during operation. The LA4 was never even warm to the touch, even after weeks of always-on use.
During my time with the LA4, its touchscreen and volume never misread an action and always behaved exactly as expected.
Benchmark warrants the LA4 for one year, extendable to five years with registration of the product.
Benchmark says that the LA4 and HPA4 are the only preamplifiers they would suggest installing between their DACs and AHB2 power amp. Luckily, I had access to the revised version of the DAC2 HGC, the DAC3 HGC, to insert in the signal chain, and to compare the LA4’s sound to that of my reference Hegel P20 preamplifier.
As usual, my Apple iMac computer, which I use as a reliable music server, streamed music from Tidal and iTunes to the Benchmark DAC3 HGC via a Nordost Blue Heaven USB link. Dynamique Audio Shadow XLR interconnects transmitted signals from the DAC3’s balanced analog outputs to the LA4’s balanced inputs, and from the LA4’s balanced outputs to the balanced inputs of an Audio Research D300 power amplifier, which drove my KEF R11 speakers via Transparent Audio MusicWave Ultra speaker cables. I left the Benchmark gear powered on around the clock, controlling both with the same Benchmark remote.
On December 24, 1968, as Apollo 8 orbited the moon, its crew read from the book of Genesis to a television audience on Earth. “In the beginning God created the heavens and the Earth,” astronaut William Anders intoned. The recording of Anders’s reading has been used by many artists over the years, including guitarist and composer Mike Oldfield. It appears in the original version of “Let There Be Light,” from Oldfield’s The Songs of Distant Earth (1994), and in a remix of the track, by Oldfield and Torsten “York” Stenzel, from the 2013 album Tubular Beats (16-bit/44.1kHz FLAC, Ear Music/Tidal). The remix begins with soft electronic undertones filling a very broad, deep soundstage and spreading out beyond and behind my big KEF floorstanders. Anders’s close-miked voice, originally beamed some 239,000 miles from Moon to Earth, had little chance of sounding like anything other than a distant walkie-talkie. But that 51-year-old recording was placed precisely at the center of the soundstage, very much forward of Oldfield’s electronic soundscape, and both elements sounded authentic, despite the 26 years separating their recording. As the piece grows, the sharp attack of a rim shot marks time while mimicking the 1968 recording, and the LA4 re-created it exquisitely. The LA4 reproduced the Oldfield track without any added emphasis -- its sound was incredibly neutral.
Another recording that caught my ear during my time with the LA4 was a remix of a track from Camouflage’s The Singles (16/44.1 FLAC, Island/Tidal). “The Great Commandment (7” Version -- Remastered 2014)” has some interesting additions not found in the 1988 original. The second time through, I realized that I was hearing a mashup of parts recorded, again, 26 years apart. The LA4 didn’t present these disparate elements as a homogeneous whole. Instead, the dramatically different new bits, especially the introduction, stood out as clean, articulate, punchy, deep-slamming electronica in comparison with the dreary original recording from 1988, which was marked by a sullen, somewhat soft and relaxed sound. The contrast wasn’t subtle -- the LA4 was exceptionally revealing, unapologetically exposing this mix as deeply mediocre. It was unforgiving to sub-par recordings. If you want a preamp that editorializes, look elsewhere.
But with well-recorded music the LA4 was exceptional. Depeche Mode’s Exciter (16/44.1 AIFF, Reprise) is a terrific example of their musical style, and lead singer Dave Gahan’s voice in “Dream On” sounded particularly splendid through the Benchmark. The LA4 revealed his breathy inhalation before launching a line, as well as the palpable hiss of his quick exhalations. Gahan’s mouthiness on or near the microphone, and his acute sibilants, were both audible, with a serious power behind his voice that I found enticing. I was especially taken with the presence of Gahan’s voice: There he was in my room, with startling clarity. The mix was brighter and much more prominent than either of the older selections above. Gahan’s voice was right there, dead center, in front of the band, ostensibly leering at me as he leaned on the mike. Like that vocal, the drums and deep bass also had excellent impact and strength. The Benchmark’s transparency was remarkable.
Dave Gahan’s powerful, virile singing is the sonic opposite of a baroque piece for flute and orchestra played on period instruments. The quiet plucking of delicate harp strings and the warm, embodied midrange of a flute are both on display in the first few minutes of Telemann’s Suite for Recorder (or Flute), Strings & Continuo in A Minor, TWV 55:a2, performed by flutist Paige Brook and the deNeveu Ensemble (16/44.1 FLAC, NY Philomusica/Tidal). I’ve played this piece, and quite enjoyed the flute’s sound though the Benchmark. Though it wasn’t recorded closely enough to capture breath noise or embouchure, the rest of the details were spot on. Higher-pitched tones sounded as expected, and tended to grow naturally more harsh with the increasing brightness of the higher end of the flute’s range. But most important, through the LA4 there was no emphasis of any part of the sound over the rest of the audioband. I heard only what was present in the recording -- nothing more, nothing less.
My reference Hegel Music Systems P20 ($2900) is priced similarly to the Benchmark LA4 ($2499), but the two preamps behaved very differently. The Benchmark has a touchscreen, computerized control of many features, and a relay-controlled volume knob, while the Hegel has no screen, no advanced functionality, and separate knobs for volume and input selection. Functionally, however, each preamp provides just two purposes for daily use: volume control and source selection.
Almost everything about the P20’s sound was different from the LA4’s. Its soundstage was roughly as wide but ultimately deeper than the Benchmark’s. Mike Oldfield’s guitar and electronics were farther behind Astronaut Anders’s reading from Genesis than through the LA4. Additionally, Anders’s voice was less strident through the P20, giving me the impression that the Hegel was rather more relaxed and laid-back than the neutral-sounding Benchmark. And the P20’s softer, more polite sound imbued that weak Camouflage recording with a bit more continuity.
Similarly, the disparity in sound quality between the two source recordings used in “The Great Commandment” was less vivid through the Hegel than the Benchmark, and Dave Gahan’s sibilants and vocal power in the Depeche Mode track was more reserved and less sharply defined through the Hegel. I’ve always loved the bottom-end slam of the P20’s sound, and found the LA4 equally generous in that regard. The Hegel’s midrange had a sweetness that contrasted with the more evenhanded Benchmark. Overall, the Hegel P20 is the more musical preamp; the Benchmark LA4 remained steadfastly neutral, occasionally bordering on analytical.
I wanted to hear how the Benchmark duo of DAC3 HGC and LA4 would compare to the DAC3 HGC alone, run straight into my ARC D300 power amp using the DAC3’s built-in preamp circuit. I found that using the DAC3’s volume control resulted in a sound similar to the LA4’s, but edgier and less refined. I wasn’t surprised that two devices performing identical volume and switching tasks, and designed and made and voiced by the same manufacturer, would sound similar. The edginess primarily revealed itself in Paige Brook’s flute, whose sound began to lean to the bright side of neutral, and in Dave Gahan’s vocal sibilants sizzling just a bit too much. Furthermore, the DAC3 HGC sounded a bit closed-in by comparison, with a slightly narrower and shallower soundstage than when the LA4 was in circuit. Finally, the DAC3 produced less bass impact in my mildly damped listening room, especially with the bass-heavy Depeche Mode and Oldfield tracks. Removing the LA4 from the signal path produced a noticeable difference in the sound, and not for the better.
Benchmark Media Systems’ LA4 preamplifier presented an utterly realistic reproduction of what was contained on each recording I played through it -- and weak recordings stood out more than usual. The LA4’s clean, analytical abilities are unmatched by any similarly priced preamplifier I know of. The LA4’s touchscreen brings it up to date with current user interfaces, and permits functions, such as balance control and muting at the device, that, say, my Hegel P20 preamp doesn’t. If, like me, you value a high-resolution, totally neutral musical performance, add a Benchmark LA4 to your system, particularly if you already own a Benchmark DAC.
. . . Erich Wetzel
- Loudspeakers -- KEF R11
- Preamplifier -- Hegel Music Systems P20
- Amplifier -- Audio Research D300
- Source -- Apple iMac running OS10.11.6, iTunes, Tidal HiFi music-streaming service
- Digital-to-Analog Converters -- Benchmark Media Systems DAC3 HGC and DAC2 HGC
- Speaker cables -- Transparent Audio MusicWave Ultra
- Analog Interconnects -- Dynamique Audio Shadow (XLR), Transparent Audio MusicLink Super (RCA)
- Digital link -- Nordost Blue Heaven (USB)
Benchmark Media Systems LA4 Preamplifier
Price: $2499 USD; remote control, add $100; rack-mount faceplate, add $200.
Warranty: One year, parts and labor; five years with registration.
Benchmark Media Systems, Inc.
203 E. Hampton Place, Suite 2
Syracuse, NY 13206
Phone: (800) 262-4675