February 15, 2009

Benchmark DAC1 Pre Digital-to-Analog Converter and Preamplifier


A company that names itself Benchmark has got to have great confidence in its products. Such a name is not so much a noun as a challenge, a line drawn in the sand that says, "We know we’re good." It’s also a dare to other makers of digital audio equipment to pit their best against a Benchmark and let the best DAC win.

The "bench" part of the corporate identity of Benchmark, which is based in Syracuse, New York, reveals something about the company and its products. Benchmark began as a supplier of professional-grade audio products for musicians and recording studios. They maintain that line of products to this day, and the influence of the pro-audio world is easily detectable in every Benchmark product made today.

The DAC1 Pre ($1595 USD) has been converting digital signals to analog in my reference system for several months now. But when I received the review sample, I didn’t know much about it or its manufacturer. When I opened the box, I was surprised at how small and light it is: its upper surface can be covered almost entirely by two CDs. The DAC1 Pre weighs 3.5 pounds and measures just 8.5"W by 1.725"H by 9.5"D. A height measurement carried to three decimal places shows how important precision is to the engineers at Benchmark.

As its name implies, the DAC1 Pre is both a D/A converter and a preamplifier. It’s remarkable enough that Benchmark can fit two separate audio components into such a small chassis; it’s more remarkable that the DAC1 Pre is one very serious piece of high technology. If there’s a technology that can improve D/A conversion that hasn’t been included in the DAC1 Pre, I don’t know what it is.

Benchmark describes its DAC1 Pre as a device of 24-bit/192kHz resolution that features two proprietary Benchmark digital technologies: AdvancedUSB Audio and UltraLock. AdvancedUSB Audio allows the DAC1 Pre to accept 24-bit/96kHz digital signals via its USB input while UltraLock is Benchmark’s jitter-reduction circuitry.

Like other Benchmark products, the DAC1 Pre is equipped with the company’s highly regarded HPA2 headphone amplifier. And, of course, it includes a preamplifier circuit to provide gain in the absence of a downstream preamp. The DAC1 Pre has a rear-mounted three-way toggle switch that permits selection among a calibrated (fixed) output level that bypasses the volume control, a variable setting that responds to the front-mounted volume knob, and Mute. The DAC portion of the DAC1 Pre has five digital inputs (three S/PDIF, one USB, one TosLink), while a single analog input is also included to facilitate the connection of another audio source. The DAC1 Pre has one set each of RCA and balanced XLR outputs, and the power connector is a standard 15-amp IEC type. About the only thing the DAC1 Pre lacks is a remote control, which likely reflects the fact that Benchmark makes most of its equipment with studio professionals in mind.

Benchmark says that the DAC1 Pre adheres to the company’s "always on" design philosophy. This includes an automatic mute function should the DAC encounter an error in the datastream, and power-management circuitry to place the device in low-power mode when no connected digital source is turned on. Nonetheless, should the user wish to completely power down the DAC1 Pre, its source-selector knob is also a push-on/off power switch.

The excellent owner’s manual offers as much information as any I’ve seen, while being an easy read that’s not overloaded with technical terms.


My reference Simaudio Moon i5.3 integrated amp served as the foundation of a revolving test system that included no fewer than four different loudspeakers: the PSB Synchrony 2B, PSB Imagine B, Focus Audio FC7, and, right at the end of the review period, the brand-new Paradigm Studio 60. Most of my listening impressions were made using the Focus FC7s, but the Benchmark DAC1 Pre performed excellently with all of the speakers.

My other system stalwart was a laptop running Windows Vista and Foobar2000 playback software. Rips were all uncompressed WAV files copied via Exact Audio Copy software, with the exception of two 24-bit downloaded recordings provided for this review by Linn Records. At first I used a Kimber Kable USB cable ($42.50) to connect my laptop’s USB port to the DAC1 Pre, but after a couple of weeks replaced it with the significantly more capable Synergistic Research Tesla Tricon USB cable ($550, to be reviewed in "The Digital Domain" on SoundStage!). Comparison USB D/A converters were an Audio Note Kits DAC2.1 Level B ($1699) and a Blue Circle USB Thingee (from $169). Power cables to the DAC1 Pre and Simaudio Moon i5.3 were by Synergistic Research, in the forms of their T2 ($660) and T3 ($950), respectively. Speaker cables were Supra’s Ply 3.4/S.


That some new component allows a reviewer to hear details in a recording that he or she had never noticed before is almost a cliché. I say "almost" because, though the refrain is a common one, it’s often an accurate description of what actually happens -- and is especially accurate in describing my experience with the Benchmark DAC1 Pre.

The first place I noticed music where I’d heard none before was in Metallica’s classic and monumental "Enter Sandman," from Metallica (CD, Elektra 61113). Before I got to the fadeout at the end, I was already impressed with the Benchmark’s ability to convey the track’s raw energy, and was reveling in its thundering bass lines and arena-concert-big electric guitar. As odd as it may sound, through some D/A converters this song can sound subdued -- perhaps restrained better describes the phenomenon. Not with the DAC1 Pre. I’ve listened to "Enter Sandman" dozens of times, and not once had I ever heard the washed-out guitar solo in the background during the fade. It was such a surprise that I muted the amp, just to make sure that a radio elsewhere in the house wasn’t playing. The experience was awesome.

Older recordings are a great place to listen for information hitherto hidden, and two of my favorites come from 1959 and Columbia Records: Dave Brubeck’s Time Out (CD, Columbia/Legacy 65112) and Miles Davis’s Kind of Blue (CD, Columbia/Legacy 64395). There must have been something in the water that year, because both recordings are simply amazing -- and I’m not just talking about the music. I’m not sure speaker technology was nearly advanced enough to convey either of these recordings in all their majesty when they were new, but today’s technology gets more out of them than anyone has the right to expect from recordings made half a century ago.

Benchmark served up another surprise for me when I played the title track of the Brubeck, a recording I’d thought I was intimately familiar with. But I was wrong -- the DAC1 Pre shone a light on a series of single tom-tom hits during Joe Morello’s drum solo that were news to me. I couldn’t imagine how I’d ever missed them, until I switched from the Benchmark to the Audio Note Kits DAC2.1 Level B, and they were gone again. Nor was it just some obscure drum accents that were new -- the entire track had a freshness that again had me marveling at the accomplishments of those late-1950s recording engineers. It’s almost sad that we’ve had to wait so long to get the full measure (or maybe not, even now?) of recordings such as Take Five and Kind of Blue, but for now, I’m thrilled with the result.

At the beginning of "So What," the opening track of Kind of Blue, Bill Evans’s piano and Paul Chambers’s double bass play one of the best-known passages in all of jazz. In my experience, the series of solo bass notes Chambers plays just before sliding his way into the song proper almost always collide with one another. The effect is a jumble of muddled and ill-defined notes. Before inserting the DAC1 Pre (and the Tesla Tricon USB cable) in my system, I thought the confusion of notes was on the master tape. I’m happy to say that it’s not. The Benchmark somehow cut through the muddle to clearly reveal each and every note -- so clearly that I literally shouted in surprise. It used to be my habit to play "So What" to see how well a given component dealt with the bass jumble, but only now do I know just how tough a test this track actually is. In my system, the DAC1 Pre has set a new, um, benchmark.

The DAC1 Pre did very well with modern recordings, too. Linn Records is among the few international music labels to permit downloads of high-resolution recordings from whatever country you happen to be in, even Canada. So it was to Linn that I turned for 24-bit/96kHz audio files to test the Benchmark’s hi-rez credentials.

Because the DAC1 Pre is a native 24-bit D/A converter, it required no special setup to take full advantage of Linn’s Studio Master recordings, other than my changing Foobar2000’s default output word length from 16 to 24 bits, as instructed by Benchmark’s very helpful Wiki, which offers optimal setup tips for many types of audio-player software.

Hi-rez 24/96 files are much larger than their 16/44.1 brethren. Claire Martin’s Dreamsville (download, Linn Records) is 258MB in 16-bit lossless FLAC format, while the 24/96 Studio Master version is almost four times bigger: 1GB. Does this mean that the 24/96 recording contains four times as much information as the "Red Book" version? That’s hard to say for certain, but the detail, clarity, life, imaging, spaciousness, and soundstaging of Martin’s beautifully and intoxicatingly performed cover of "It Never Entered My Mind" all seemed to point to a great big YES! Once you go 24-bit, it’s hard to quit (™ © Colin Smith, 2009). Plain old 16-bit tracks sound, well, plain and old in comparison. I can’t wait for the 24-bit remasterings of Kind of Blue and Time Out.

As superb a D/A converter as the DAC1 Pre was, I had to remember that it’s also a preamp and a headphone amp. Unfortunately, I don’t have a good set of headphones for review purposes, so I can only assume that the HPA2 headphone circuitry is as good as the rest of the DAC1 Pre. (That’s a big hint to let you know that the preamp section is excellent too.) I was able to try out the Benchmark’s preamp section by virtue of the flexibility of my Simaudio Moon i5.3 integrated, whose preamp circuits can be bypassed to allow the i5.3 to be used only as a power amp. It made comparing the i5.3’s and Benchmark’s preamp sections as easy as flicking a switch.

It wasn’t always possible for me to tell the difference between the preamp sections because they both performed at a high level. Where there were differences -- mostly in the level of crystalline clarity each offered -- they were slight and, I think, probably had more to do with Simaudio’s optical-relay volume control, which keeps the signal path short and pure, vs. what I believe is a potentiometer in the Benchmark. Whatever the reason, it was evident that the preamp built into the DAC1 Pre is a high achiever. It was neutral, conveyed a realistic soundstage, and offered imaging on a par with its DAC roommate. If it were a standalone preamplifier, it would be an easy recommendation for the $1000 price point. The absence of a remote control is surprising in a device containing a preamp, especially in light of Benchmark’s otherwise thoroughgoing approach to design. It makes me wonder if a remote was left out simply because there was no room left inside the chassis to accommodate an infrared receiver.


The DAC1 Pre was put up against the two other USB D/A converters I had available, the Audio Note Kits DAC2.1 Level B and the Blue Circle Thingee. The comparison wasn’t on an entirely level field -- the DAC2.1 has a tube output stage while the Benchmark is solid-state, while the Thingee is far less expensive than the Benchmark and lacks a power supply of its own, drawing its 5V from a computer’s USB bus. But, as they say in racing, "run what you brung."

The Audio Note is much more laid-back than the Benchmark. It doesn’t sound lazy or as if it can’t keep up with the music, but it’s a mellower, elbow-patches-on-tweed-jacket kind of DAC. It does very well with jazz and the fuzzy rock of the 1960s and ’70s, and is a commendable performer when it comes to retrieving detail, but, especially on that last point, it’s not in the same game as the DAC1 Pre. The Benchmark never sounded etched or sterile in comparison to the warmer Audio Note, but it was more musical, and more true to recorded instruments and voices.

Blue Circle’s USB Thingee is a fantastic performer, not only for a device that’s incredibly inexpensive, but as a USB DAC period. It has its limits, the chief one being that it relies for juice on a computer’s never-pure power supply. Blue Circle takes pains to clean up that power through their innovative use of a built-in power conditioner, but there’s no substitute for a dedicated power supply, as is found in the Benchmark. Blue Circle’s new Thingee HO (for High Output), complete with its own power supply, will arrive here soon, and will make for a very interesting comparison with the DAC1 Pre. But for now, it almost goes without saying that, as good as the Thingee is, it doesn’t compete with the Benchmark. Nor should it, for $169.


From the moment I set it up until I very reluctantly sent it out to be photographed, the Benchmark DAC1 Pre was a stellar performer. It did it all, and did it extremely well. Despite its aptitude for detail retrieval, it never sounded hard or artificial -- in fact, quite the opposite. This is one audio product that will breathe new life into old recordings you thought you knew intimately, and it’s among the very few components I’m comfortable recommending without advising a listen before buying. The DAC1 Pre comes back from the photographer tomorrow, and that will be its last trip outside. I wouldn’t let this thing go for love or money, but I’ll spend some to keep it.

. . . Colin Smith

Price of equipment reviewed