Building upon the successes of their DAC1, Benchmark is not resting on their laurels. The release of the DAC2 series of products extends the capability and sonic performance of the product line with several different versions, offering a wide range of functionality to suit different owners’ needs.

While it might be easy to get confused by so many variations on the DAC2 theme, it’s important to note that all contain an improved digital engine. The primary differences are inputs and outputs, headphone capability and home theater pass-through. Two versions of the DAC2 come equiped with headphone outputs: DAC2 HGC and the DAC2 DX. DAC L and DAC HGC incorporate single-ended analog inputs for use as a preamplifier. The DX model we tested for this review includes an AES/EBU digital input, but no analog inputs.

Like its Benchmark ABH2 Amplifier we just reviewed, the DAC2 comes in a small enclosure with a lot packed inside. Measuring a scant 9.5 inches (249mm) wide, 9.33 inches (237mm) depth and a 1.725 inches (44.5mm) in height, the DAC2 is small enough to place anywhere easily, even on the most crowded audio racks. Plus, at a mere 3 pounds in weight, it’s easy to lift with one hand when placing it – a real joy after helping our publisher crate up the 274-pound Boulder 2160 the other day!

Internal Innovations

Under the hood, digital processing prowess is provided by SABRE DAC chips to decode 32-bit PCM and DSD files. Feeding these converters the best possible signal, Benchmark utilizes its new jitter-reduction technology via their UltraLock2™ system – a dramatic improvement over the original version in the DAC1. Focusing on lowering the noise floor and distortion level, the latest changes prove highly effective. The variable output makes the DAC2 more versatile than a DAC without, and makes it easy to become the cornerstone of a compact, yet high performance system, eliminating the need for a standalone linestage.

The back panel of the DAC2 reveals a plethora of connections fit to this tight space. Inputs include USB, two coaxial digital, and two optical connections. For analog output, the options depend on the DAC2 model chosen. All models have two pairs of single-ended outputs, and one pair of XLR balanced outputs. With the analog input equipped HGC and L models, the DAC2 features a HT pass through too.

You might not earn carbon offset points with your stereo system, but as a tree-hugging Oregonian, I appreciate that the DAC2 only draws half a watt at idle.

Snappy Setup

The DAC2 is extremely easy to set up. My Mac Mini instantly recognizes it, only requiring a few quick tweaks in the Mac OS sound settings to be ready to play music. Benchmark promises the same ease on the Windows side. While we did not have a Windows-based system on hand for testing, Benchmark has worked to make that experience just as seamless. For high resolution playback on Windows, an easily downloadable driver is needed.

Tight real estate on the rear panel is the only issue that has always plagued Benchmark DACs. As such a small unit, with so many input and output choices, the DAC2 rear panel is a bit crowded. If you have thick audio cables be aware that you may find it a bit of a stretch to get them connected. Lastly, those utilizing 24/192 or DSD files via USB will need to hold down the USB button on the remote for three seconds (a one-time setup operation) to engage USB 2.0 mode for the best performance.

Locked-in listening

When I’m anchored into my listening seat, the beefy aluminum Benchmark remote proves a couch potato’s dream come true. The ability to change inputs, volume, and mute leaves little need to get up.

After several days of burn-in, it’s exciting to give this DAC a chance to sing. From the first listen, DAC2 provides a treat for the senses with a highly resolving, yet forgiving nature. Regardless of music type, DAC2 performs as a sonic chameleon rocking and rolling when it needs to, but is equally at home with the delicate nuances of jazz and classical recordings.

Cat Power’s Jukebox illustrates how the DAC2 picks up every pluck of the guitar, keeping them appropriately separated from the vocals, which reside in a different vertical plane parallel to the first. The resonance and decay of acoustic guitar notes are easily discernible across several other recordings too, like Elliott Smith’s XO – his vocals retaining a smooth, organic quality. While DAC2 may not recreate quite the level of transparency reproduced by more expensive DACs I’ve heard, I really like the voice Benchmark engineered into the DAC2. Overly transparent and revealing equipment can tend toward stridency, sibilance and a wince-factor that takes away from the musical experience.

The DAC2, on the other hand, allows a listener to dissolve into the music and enjoy big, beautiful sound rather than getting bogged down in the minutia. For example, several songs on Portishead’s album Dummy have a glare that draws attention to those sharp edges rather than the rounded musical picture. With the DAC2, those sonic artifacts are not removed, but the entire album is much more listenable.

DAC2 also throws a huge soundstage and mines a lot of ambient detail from high-resolution recordings. The perceived stage width and depth easily exceeds the speaker boundaries in all directions. Also, DAC2 projects a sonic image that reaches from floor to ceiling. Many DACs I’ve heard do a good job of this, but so far, I have not heard one under $2,000 that does it so well.

Hearing Headphones

Rather than tossing a headphone amplifier into the unit as an afterthought, Benchmark took great care in delivering a high quality headphone amplifier in the DAC2. Those considering a Benchmark DAC for headphone listening should consider taking advantage of the company’s special pricing offer which bundles a reduced-cost set of Sennheiser HD-650 headphones with some versions of the DAC2 . Those headphones are among my own favorites, and a reduced-cost package through Benchmark is an added bonus for a DAC2 owner, not to mention a great place to start your headphone journey.

With a set of HD650s on hand, listening begins with the Benchmark-recommended cans. While very resolving, the Sennheisers are a bit to the warm side of neutral. As expected, the quality of the DAC2’s sound proves revelatory with any music being piped out. Especially enjoyable are the ease and naturalness of the sound. Electronica like Phantogram’s “Black Out Days” has plenty of punch and detail, but not at the expense of the bigger sonic picture. As an older recording, guitar on Albert King’s Born Under a Bad Sign can have some sting, but the DAC2 pulls the best from it.

When I switch to a set of Audeze LCD-X headphones, the DAC2 demonstrates plenty of power to drive them, delivering the bass punch these headphones are capable of producing with the right setup. Sonically, these headphones are like stepping forward several rows in an auditorium, getting up close and personal with every bit of the performance. For me, this action-packed delivery was perhaps too close and personal, and I found myself preferring the Sennheisers for the bulk of my listening. The HD-650s indeed seem a perfect match for this setup, and I can see why Benchmark recommends them.

In the end, excellent

$1,895 is not a small price tag, but in a hobby offering mega-buck DACs, it’s a modest sum for a component of this caliber. The DAC2 is a very easy component to live with sonically and aesthetically. Its versatility takes the value to another level, making me nominate this one for an Exceptional Value Award and give it an enthusiastic recommendation.  -Rob Johnson

Additional Listening

You have to go back almost seventy issues of TONE to our third issue for our first encounter with Benchmark. The original DAC1 was $995 and garnered our first Exceptional Value Award. It was a class leader then and it remains so today.

Staff member Jerold O’Brien still has his DAC1, so it was enlightening to compare it with the DAC2 alongside. Much like what we found comparing the Nagra PL-P to the current Jazz, the compact exteriors, as well as the overall sound, are very similar. Benchmark gear has always been very neutral, and like Nagra, because they supply so much equipment to the studio world, has little room for embellishment.

The trademark lack of sound that is Benchmark comes through instantly, but stepping up to the DAC2 immediately reveals more music and a deeper insight into recorded material, standard or high resolution. Remember, ten years ago we weren’t even talking about high resolution files, let alone DSD, so moving on to that realm is even more enlightening.

I’ve always loved using Benchmark DACs as a linestage and again, the DAC2 does not disappoint. Auditioning it with everything from a 35 watt per channel PrimaLuna ProLogue 4 up to the mighty Boulder 2160 reveals just how good this component truly is. The DAC2 is perfect for a primarily digital user who wants to put the preamp up on the shelf and run some interconnects to a power amplifier elsewhere in the room – the DAC2 drives long interconnects with ease.

So, ten years later, Benchmark continues to create an awesome DAC in a compact case. I’m guessing I’ll have to arm wrestle Mr. O’Brien for it again. -Jeff Dorgay

Benchmark DAC2 DX

MSRP: $1,895

Benchmarkmedia.com

PERIPHERALS

Digital Sources	Mac Mini with jRiver and Roon playback    dCS Debussy
Amplification	Burmester 911 mk3
Preamplification	Coffman Labs G1-A
Speakers	Sonus faber Olympica III
Cables	Jena Labs
Power	Running Springs Audio Haley, and RSA Mongoose power cords
Accessories	ASC tube traps    Mapleshade Samson audio racks    Coffman Labs Equipment Footers    AudioQuest Jitterbug

The first thing you notice about the new Benchmark AHB2 is its diminutive size. Even with feet and binding posts, it’s only about 11 inches wide, 4 inches tall and 9 inches deep. And the heat-sink fins account for about a third of that width, making it even more incredible that Benchmark was able to jam so much oomph into such a small body. Regularly lifting amps that leave my back barking for Tylenol, I chuckle with relief when carrying the 12.5-pound AHB2 to my audio rack.

At about $3,000, the Benchmark AHB2 is a substantial investment, and it certainly demonstrates many musical characteristics one would expect at this price point. But the amp’s size makes it appealing when shelf space is limited or when you simply want to minimize your gear real estate. If more power is desired, you can buy a second AHB2 and configure them as monoblocks.

Benchmark offers the unit with a black or silver anodized faceplate and black heat-sink fins. A studio version is also available, with a wider front plate to fit equipment racks. Other than its tiny power button, the front of the amp has no other controls, just a few LEDs to indicate aspects of operation. Each channel has three LEDs to indicate clip, temperature and mute. In the event of an amp overload (which happened once during my testing), the amp shuts itself down and the LEDs indicate the nature of the problem. Powering the unit off, waiting a few seconds and pressing the power button puts the amp back into operational mode.

Setting the Benchmark

As Benchmark products are used regularly in recording studios, all of the AHB2’s connections are balanced. A couple audio designers have explained to me that balanced XLR connections usually prove superior to single-ended RCAs, since XLRs offer inherent noise canceling and they won’t come loose once clicked into place. If the rest of you’re system doesn’t offer XLR connections, Benchmark also makes cables and adapters.

Setup is fairly straightforward: Connect a preamp and speakers, ensure the stereo/mono toggle is set to the desired position, and then set the three-position sensitivity switch to match the signal levels from your preamplifier; the sensitivity switch also optimizes the amplifier’s gain for controlling volume from your preamplifier. Because of the amp’s size, its back panel can get crowed, making connections a little tricky—especially with my speaker cables, which have soldered spade connections that don’t bend. As such, I have to place the amp at the back edge of my audio shelf so the cables can hang below the amp (though I’ve had this same problem with other amps I’ve tested).
The AHB2 also offers twist-lock NL4 ports for speaker connection. Benchmark says NL4s provide lower resistance and higher current handling than connection via binding posts, as well as a more secure connection. As most speakers don’t have an NL4 connection option, Benchmark makes speaker cables with NL4 connectors for the amp side and standard connections for the speaker side.

Once everything is connected, simply push the power button on the front panel to activate the start-up sequence. When configured as a stereo amp, the AHB2 pushes out 100 watts into 8 ohms and double that into 4 ohms. For those wanting a 12-volt trigger for remote power-up, the AHB2 has you covered.

The AHB2 features a Class-AB/Class-H design (hence its name), which facilitates bridging a pair of the amps to use as monoblocks, pushing 380 watts into 8 ohms. This scenario is very useful if your speakers need some extra juice and you want to provide a dedicated amp for each, or if you want to drive a center-channel speaker in a home-theater setup. When using this setup method, consult the manual to ensure the proper connections and settings.

Meeting the Benchmark

Among Benchmark’s design goals for the amp were extremely low distortion and quiet operation. From the get-go, the amp lives up to its design specs by providing a very clean presentation. The Benchmark does a good job of layering vocals and instruments in all dimensions, with each element supported by a solid and convincing image. The amp’s designer, John Siau, is quick to mention that the third goal was to achieve a ruler-flat high-frequency response—and the AHB2 is completely flat all the way up to 200 kHz. Siau says these qualities are vitally important in delivering high-resolution performance.

As desired in a studio setting, the sonics from the AHB2 are neutral, and in my home setup, there is no observable emphasis in any particular frequency range. I would not characterize the AHB2 sound as warm or romantic, though it’s not stark or emotionless either. Between these two ends of the spectrum, the amp leans toward the latter but with a sweeter top end. Those seeking an amp that emphasizes fullness and richness that will augment slightly thin sound from your preamp or source might consider other amp options. But if accurate portrayal is a listener’s goal, this Benchmark does the trick.

When reproducing poor-quality recordings, the AHB2 does a nice job of limiting digital glare. Lucinda Williams’s album Car Wheels on a Gravel Road demonstrates the AHB2’s ability to offer edge-free portrayal of vocals with a very fluid midrange. Her voice resides upfront in the soundstage and it is well separated from the instruments accompanying her.

Regardless of music type, bass through the Benchmark offers a taught presentation with the snap and punch one expects from percussion. Depeche Mode’s “Personal Jesus” is engaging through the AHB2, with all the subtle synthesized sounds popping into position in the soundstage. This makes me curious about running a pair of the amps as monoblocks—which still wouldn’t take up the rack space of a single traditional amplifier.

The Benchmark brings to life the voice of the Martin Logan Motion XT35 bookshelf speakers. Considering its recording-studio applications, it makes a lot of sense that this amp pairs well with smaller stereo monitors. Combined with the speakers I have on hand for testing, the AHB2’s sound flavor profile remains consistent.

In the case of the AHB2, system synergy is an important factor to consider, since no amp is universally perfect for all speakers. For large and demanding speakers, a prospective AHB2 owner may need more power. In the case of the AHB2, you can add another unit and configure the two amps as monoblocks.

Additional Listening

By Jeff Dorgay

I was curious to hear how Benchmark’s design ethos of compact products would translate into designing a power amp. A couple years ago, the Devialet shattered my bias that amplifiers had to be massive to sound good, and so today I find myself much more open-minded to smaller amps like the Benchmark.

My initial exposure to the AHB2 was at this year’s Rocky Mountain Audio Fest, where Benchmark was playing the amp in an all-Benchmark system that included its new mini-monitor speakers. Back in my own listening rooms, the AHB2 did a fantastic job driving the KEF Blades, Dynaudio Evidence Platinums and even my Acoustat 2+2s, which are notoriously tough to drive, though a pair of AHB2s would have been even better for the 2+2s.

As both my reference systems are balanced, I actually prefer the XLR connections of the AHB2. If you’re working with single-ended RCAs connections, the Cardas adaptors are my favorite. I agree with Rob’s conclusions on tonality, etc., and will add that the AHB2 definitely has the bass drive necessary to achieve convincing full-range performance, even from big speakers.

In the end, the Benchmark AHB2 can become a great anchor to your system, offering high performance in a compact box. With an extremely neutral tonal balance, you can use it straight, or warm it up with a tube preamplifier, should that be your preference. Either way, the AHB2 is a stellar performer from a company known for excellence.

Benchmark AHB2 power amplifier

MSRP: $2,995

benchmarkmedia.com

PERIPHERALS

Digital Sources	Mac mini, dCS Debussy DAC    JRiver Media Center 20    Tidal music service
Analog source	SME 10 turntable with SME 10 tonearm and Dynavector 17D3 cartridge
Amplifier	Burmester 911 MK3
Preamplifier	Coffman Labs G1-A
Speakers	Sonus faber Olympica III, Martin Logan Motion XT35
Cables	Jena Labs
Power	Running Springs Audio Haley power conditioner    RSA Mongoose power cords
Accessories	ASC tube traps    Mapleshade Samson audio racks