Go to Home Page

Click Here to Go to Index for All DACS and Digital Processors

 

Product Review
 

Benchmark DAC-1 DAC/Preamplifier

Part I - Introduction, Design, and Listening

November, 2003

Jason Victor Serinus

 

Click the Photo Above to See a Larger Version

Specifications:

 

2-channel, 24 bit, 96-kHz D-to-A conversion
192-kHz playback with 48 kHz analog bandwidth
THD+N = -106 dB (0.0005%) measured at -0 dBFS
116 dB signal-to-noise ratio @48 kHz, A weighted
AES/EBU (XLR & Coax) and S/PDIF (XLR, Coax, & Toslink) inputs
Digital input source-selection switch
Balanced, low-Z XLR outputs
+29 dBu output level capability
Unbalanced RCA outputs
Variable or preset output level controls, switch selectable
Direct connection to powered monitors
Built-in Benchmark HPA-2, a high-output, ultra-clean headphone amplifier with dual outputs jacks
Automatic De-emphasis for 44.1, 48, 88.2, and 96 kHz when Pre-emphasis bit is set

Size: 1 3/4" H x 9 1/2" W x 9 1/3" D
Weight: 3.5 Pounds
MSRP: $850 USA

 

Benchmark Media Systems, Inc.

www.benchmarkmedia.com
 

Introduction

Early in 2003, recording and mastering engineer Bob Olhsson, famed for his work on “The Motown Legend”, told me about Benchmark Media’s diminutive, amazingly low-priced unit. In doing so, he echoed the praises of recording engineer Bob Katz, long associated with Chesky Records, who had initially turned him on to the DAC-1.

Gushing quotes from both engineers have since joined a host of other professional endorsements that are posted on Benchmark’s site. Olhsson notes: “This thing has outrageous bass reproduction and as good a sense of image and depth as I have ever heard including vinyl…”

Katz, formerly associated with Chesky and now with Digital Domain writes: “The Benchmark is a killer!… I've NEVER heard a $850 DAC that sounds as good as this Benchmark. It has definitely established a new price/performance ratio.”

While I’ve never met Katz, I have been friends with Olhsson for many years. Not only was I well acquainted with his listening set-up during the time he lived in Northern California, but I have also reviewed a number of recordings he has mastered for Hearts of Space. Knowing his high standards, I take his comments seriously.

It took less than a month for me to contact Allen Burdick of Benchmark Media and obtain a DAC-1 for review. Burdick was quick to explain that the DAC-1 was designed with the recording engineer in mind. With so many low price studios churning out flat, harsh, one-dimensional digital recordings, Burdick’s goal was to provide studio engineers with a low-price option for radically improving recorded sound.

Because Benchmark’s target audience is audio professionals rather than consumers, most audiophile reviewers have steered clear of this product. Whether or not its exceptionally reasonable price, far less inflated than a lot of audiophile gear, has something to do with the cold shoulder is a matter for speculation.

As far as I know, only high-end reviewer John Marks, at least two of whose excellent JMR Recordings I have reviewed for Secrets, has commented on the unit in the audiophile press. Marks writes of the unit: “[The DAC-1 is] the lowest-priced piece of digital gear that can give sonic performance that is not just improved mid-fi, but genuinely high-end. There are less-expensive CD-playing solutions, but I think that the Benchmark (and anything else with similar performance) is at the watershed point—unquestionably among the hills that lead to the highest peaks.”

Given such praise, you may wonder why I’ve held off writing the first full-length audiophile review of this product until now. There are several reasons.

The first is that for more months than I wish to recall, I have held onto the hope that Theta Digital would finally be able to break loose a review sample of their new $10,000 Gen. VIII DAC/preamp so that I could compare it with the DAC-1. The Gen. VIII, which for all I know will arrive within a week or two of completing this review, is expected to replace my long-time venerated reference, the highly musical but unquestionably outdated Theta Gen Va. While I expect that the Gen. VIII will outshine the DAC-1 in most or all areas – it had better, given the huge price differential between the two – I remain of the belief that the virtues and shortcomings of a piece of gear are often most clearly delineated when compared to “statement” products of significantly greater cost. I thus regret that the DAC-1/Gen. VIII comparison could not be performed by press time.

Secondly, I have held off drawing ultimate conclusions about the unit until several upgrades to my system had time to settle in. Most notable of these are:

1. The replacement of my old Audio Alchemy DDS-Pro transport with a heavily modified Sony 707ES from the workshop of Alexander Peychev http://www.aplhifi.com. At least when listening to music via its AES/EBU output, the Peychev-modified Sony offers far more resolution, brilliance, transparency, and detail. Its lower noise floor, grain-free highs and tighter bass are an especial boon, enabling me to hear deeper into the heart of the music.

2. The replacement of the short power umbilical cord between Perpetual Technologies P-1A and Monolithic Power Supply with a Revelation Audio silver power cable. Especially notable is the increase in bass response. While at Allen Burdick’s suggestion I did not use the P-1A when reviewing the DAC-1, I always use it when listening to my reference DAC, the Theta Gen. Va.

3. The latest modification to my Talon Khorus X speakers. This includes the addition of Bybee Filters to tweeters and woofers, a switch to Shunyata internal wiring, a change of crossover capacitors and values – the new crossover is entirely different than the Khorus X’s first generation crossover -- and speaker repositioning. The latter was accomplished with the invaluable assistance of Bob Bergner of http://www.rbaudio.com, who used a soundcard and program developed by Rives Audio to measure the Khorus X’s frequency response and interaction with my relatively untreated listening room. The good news is that the Khorus X’s response is now remarkably flat throughout the spectrum, with few bumps and dips. The sound is far more extended on both ends of the spectrum, with much greater transparency, smoothness, and detail. This upgrade has definitely enabled me to more clearly what is going on with a particular piece of equipment. It has also granted me untold amounts of pleasure.

The Design

This teeny, lightweight baby can be variously used as a DAC/preamp or stand alone DAC. You can listen to it via speakers or one of its two headphone outputs. The unit accepts either coaxial (RCA-terminated), XLR (AES/EBU), or optical digital inputs; the loud-clicking input selector switch is located on the front of the unit.

The DAC-1 offers a choice between coaxial (RCA) and balanced (XLR) outputs, and accepts an aftermarket three-prong power cable of your choice. Output level can either be set to “Calibrated,” in which mode it is adjusted via little screws on the rear of the unit and the volume control on an external preamp, or to “Variable.” In “Variable” mode, when the unit functions as both DAC and preamp, output level is controlled by the volume control on the front of the DAC-1. This volume control also adjusts headphone level.

The front of the unit includes a blue Power indicator, red Error indicator and yellow “non PCM” indicator. The lights may be acceptable for recording studios, but they are much too bright and distracting for home systems. Whenever I listened to the DAC-1, I blocked out the lights.

Since Benchmark’s website offers a complete technical description and specs, three graphs, and downloadable cut sheet and manual, I relegate parrots to their native habitat and invite you to peruse them at http://www.benchmarkmedia.com. If you don’t have Acrobat Reader, you can download it for free from Adobe.

Auditioning

Since the DAC-1 can be used either as a stand-alone DAC or all-in-one DAC/preamp, I auditioned it in both modes. When used as a DAC only, I employed as preamp the $6250 Reflection Audio OM1-Quantum in wall-power mode. (The unit comes with an optional rechargeable battery power supply that provides pure DC). My interconnects and speaker cables, save for the exception described below, were Nordost Valhalla; powercords were a combination of Elrod EPS and EPS Signature. While it is doubtful that most music lovers who spend only $850 on a DAC (let alone a DAC/preamp combo) will have a system whose other components and cables cost so much more, using expensive statement products enabled me to clearly hear the DAC-1’s characteristics.

The only problem I encountered when beginning my final round of auditions was that the DAC-1 refused to read the AES/EBU output of Alex Peychev’s transport. In e-mail correspondence with Allen Burdick, who subsequently communicated with Peychev, Burdick explained:

“We have never had any experience with the DAC muting when decoding a valid AES or S/PDIF bit stream from ANY transport. This is the first report of any muting of a signal mute other than someone sending an AC3 Dolby signal to the DAC, for which it was not designed.

“When the error light comes on the design is saying that there is a problem with the signal that it is receiving. Since this unit is, as you say, highly modified, our suspicions are that there is a problem with the AES signal that is being sent to the DAC. I checked with our chief engineer and his design will mute with only two conditions. The first is if the bit stream says it is professional and the status bit indicates a non-audio signal. The second is when data is sent in consumer mode. CRC errors will not mute the DAC. These are status bit errors.

“As far as using a different transport for your evaluations, that is just fine. The DAC was designed to be free from transport anomalies, with the exception of AES bit stream mistakes.”

I of course had the option of reverting back to my Audio Alchemy DDS-Pro, whose AES/EBU output works perfectly with the DAC-1. But since Alex’s transport allows me to hear so much more detail, and I had devoted a lot of time to carefully positioning it and isolating it from vibration, I was averse to removing it. Instead, I called into play a Nirvana BNC-terminated digital cable to use between the modified Sony transport and DAC. In part because this necessitated the use of a BNC-to-RCA adapter at the transport end, and a second adapter for the P-1A when performing comparisons, the Nirvana came across as flatter sounding and less brilliant than the Nordost Valhalla. (The Nordost costs three times more than the Nirvana). To insure that comparisons were performed on a level playing field, the Nirvana digital cable remained in the chain for all comparisons.

And then . . .

Let me correct that last statement. It should read “the Nirvana digital cable remained in the chain for almost all comparisons.” As it turned out, after I had completed my major listening comparisons and written the bulk of this review, Alexander Peychev of APL and Stephen Balliet of Reflection Audio came over to take hear how the DAC-1 sounded in my upgraded system. (Both were delighted by the sound of the upgraded Khorus X). We soon discovered that we were able to “trick” the DAC-1 into reading the signal from the Nordost Valhalla AES/EBU cable by first locking onto the Nirvana’s coaxial signal and then switching the DAC-1 to “XLR” mode. I will append my observations about what was revealed to the end of my report.

Listening

As every self-respecting critic should, I listened to the DAC-1 in ultra-critical mode. If in the end my observations focus as much on the DAC-1’s limitations as on its strengths, they should be comprehended in the larger context. We are comparing an $850 DAC/preamp either with a DAC chain (P-1A/Monolithic/Theta Gen. Va) that would now list for far more than $5000, or a DAC chain/state-of-the-art preamp that together would list for over $11,000. If the far more expensive equipment didn’t sound better than the DAC-1, something would be way off.

What I ask you to keep in mind as your read my observations is that the DAC-1 is truly an extraordinary unit.

I did not audition the DAC-1 via headphones. I don’t ordinarily use them, and none of my reference equipment has a built-in headphone jack. Without a reference, and with older headphones to boot, I decided to pass.

While I expect my reference discs will change once I have the Theta Gen. VIII and Sony XA9000-ES SACD player chez Serinus, for the moment I have stuck with selections from a group of recordings that I can safely say I canlisten to all night.

The first choice was Arleen Auger’s Love Songs (Delos), specifically Copland’s “Pastorale” and Obradors" “Del Cabello más sutil.” With DAC-1 doing double duty as DAC/preamp, I thought the sound optimally transparent. Dalton Baldwin’s piano sounded very full, albeit not as resonant as I would have wished. There was wonderful detail to the singing. But the one thing that disturbed me was the tone. It seemed all of one piece, with a somewhat glassy uniformity and a steely edge on the highs that obscured the distinct colors of piano and voice.

When I paired the DAC-1 with the Reflection Audio OM1-Quantum, the tone of both piano and voice became more rounded and full. The voice seemed more grounded, with undertones restored to their rightful place. There was also a magical sense of quietness on the Obradors that I did not experience when the DAC-1 had performed double duty. Initially I thought I had lost some transparency, but what I came to realize instead was that the Reflection Audio is a much more neutral, less edgy preamp than the DAC-1s. This may be due in part to limitations of the DAC-1’s inexpensive volume control, which is bypassed when the DAC-1 is used solely as a DAC. Regardless, having use of a preamp of the OM1-Quantum's caliber, I much preferred to listen to the DAC-1 in DAC-only mode.

The P-1A/Theta chain definitely lacked the brilliance of the DAC-1’s sound, and seemed more veiled. Such are the limitations of the Theta’s older technology and 18-bit chip. Nonetheless, the Theta (paired with the P-1A) compensated with highs more refined and magical. It may seem contradictory to suggest that something that sounded a tad veiled and less transparent nonetheless sounded more realistic, but the fuller lower midrange and bass of the Theta combined with a more refined top more clearly and accurately displayed the range of colors present in the voice and piano. I missed the DAC-1’s 24-bit, 96 khz transparency and three-dimensionality, but I preferred the greater musicality of the older, far more expensive unit.

Turning to Terry Evans’ “Blues No More” track from Puttin’ It Down (JVC-XRCD), the clarity of the DAC-1 was outstanding, but compromised by a certain lack of mellowness and midrange warmth. The results were far more in your face, with highs a bit noisy and splayed. This is not to suggest that the recording was unlistenable – compared to 99.9% of home systems, it sounded fantastic – but the bright edge on the highs, including a glassiness to the cymbals, was certainly apparent.

When the DAC-1 was connected to the OM-1 Quantum, I was blown away by the huge amounts of very tight bass I heard. The cymbals also seemed far less glassy.

With the P-1A/Theta, I sensed an even wider soundstage than with the DAC-1. As with the Auger, the diminution of transparency, brilliance and three-dimensionality was more than compensated for by a mellower, more refined and musical presentation.

It’s important to note that while my basic observations did not alter as I continued to listen, the differences between recordings helped me to further consolidate my thoughts about the DAC-1. I shall thus confine further comments to the experiences that stuck most in my mind.

George Faber’s Blues (BAT) is recorded at a higher level than any other disc I auditioned. I intentionally chose not to alter volume to discover what would happen. With the DAC-1 used either as either DAC/preamp or stand-alone DAC, I found the opening “Takes a Better Man” too noisy for my ears. The Theta lacked nothing in the way of drive and punch, but its mellower presentation, more refined highs and increased fullness on the lows more than compensated for the slight film over the proceedings. Even at high volume, I was able to enjoy the music.

“El Choclo,” the opening track on Será una Noche (MA Recordings) and the first few tracks on Karina Gauvin’s extraordinary performance off Canteloube’s Chants d’Auvergne (CBC Records) brought the striking air and transparency of the DAC-1 to the forefront. It also highlighted the unit’s somewhat mono-dimensional range of colors, an experience common with many digital components (especially preamps). By comparison, what struck me most when listening to the P-1A/Theta chain was the difference in coloration between bongos, bass, and other drums on “El Choclo” and the fabulous range of color in the chamber accompaniment to Gauvin’s incomparable singing.

As mentioned above, I was able to briefly audition the DAC-1 using the Nordost Valhalla AES/EBU cable. The gain in clarity served to further confirm my conclusions. Any DAC-1 owner with a good, neutral sounding preamp on hand (no easy task to find – I’ve been through bunches, including lots of tube changes, before I’ve found two I can live, the Bruce Moore Companion III in highest upgrade mode and the Reflection Audio OM-1 Quantum) and an extra set of high quality interconnects is encouraged to try the Benchmark in DAC-only mode. This may give you the best of both worlds for the lowest possible price.

Modifications

As in the case with many SACD players, the Perpetual Technology gear, the old McCormack DNA amplifier line, and other equipment built to a price point, upgrading the DAC-1 can result in noticeable improvements.

I have now had two brief opportunities to listen to a DAC-1 modified by Stephen Balliet of Reflection Audio http://www.reflectionaudio.com. While Stephen is reluctant to divulge all his secrets, he has told me that his modifications include adding Bybee filters, isolating the power supply, and cryogenically treating components.

To my ears, Stephen Balliet has worked wonders with the DAC-1. In DAC/preamp mode, I still find the sound somewhat monochromatic, but the highs are far more tamed and musical. The bass is also fantastic, almost on a par with the Theta Gen. Va. Used solely as a DAC, with the Reflection Audio OM-1 Quantum serving as preamp, not only does the color of instruments and voice come very close to what I’m accustomed to hearing from the Theta/P-1A chain, but there is far more transparency and three-dimensionality. The upgraded unit still lacks the last degree of Theta’s ultimate fullness and killer bass, but what it does present it presents with greater veracity and musicality than before.

Frankly, if I did not know that the Theta Gen. VIII DAC/preamp is slated to arrive chez Serinus sometime before the melting of the polar icecap – which means it had better arrive sooner than later – I would be sorely tempted to go with Stephen Balliet’s modified DAC-1. For less than a third of the price of the Theta, it performs an astounding job. For DAC-1 owners, Stephen’s upgrades are well worth considering.

Click Here to Go to Part II - On the Bench, and Conclusions

 

© Copyright 2003 Secrets of Home Theater & High Fidelity

Return to Table of Contents for this Issue.

Go to Home Page

 

About Secrets

Register

Terms and Conditions of Use