- Written by Jason Victor Serinus
- Published on 28 January 2008
Introduction: A Return Visit
I expect that many Secrets readers will already be familiar with the Benchmark DAC1. Initially brought to my attention by recording and mastering engineer Bob Olhsson, then by fellow audiophile reviewer/music critic John Marks, the Benchmark's amazingly high level of performance for a unit priced well under $1000 immediately seized the audiophile community's attention when it first came on the scene well over four years ago.
My initial review of the DAC1 Digital-to-Analog Converter appeared in these pages toward the end of 2003. As I wrote at that time, Allen Burdick of Benchmark Media explained that the DAC1, then retailing for $850, 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.
While I expressed some reservations about the DAC1's performance in my initial review, I found myself ultimately agreeing with what critics were saying. "The DAC1 is a major achievement," I wrote in my conclusion. "Far more than a taste-of-the-high-end toy, it is a bona-fide audiophile product whose sound is astonishing for its price."
Since then, the DAC1 has continued to make waves in the audiophile community. Benchmark Media has responded accordingly, embracing the home entertainment market by significantly upgrading the unit's performance while keeping the cost of the basic unit under $1000.
Perhaps a year ago, Rory Rall of Benchmark Media contacted me about revisiting the DAC1. Rory not only claimed that its sound had greatly improved, but also enticed me with the news that a new version of the DAC1, the DAC1 USB. This new model includes a USB port for connection to computers and hard drives. The USB input is compatible with Windows Vista/XP/2000 and Mac OS X, and does not require driver installation or system configuration.
Given that my main system's Theta Gen. VIII DAC/preamp does not have a USB port, I leaped at the opportunity to connect my Apple Powerbook laptop to my main system. I was also enticed by the idea of adding an external DAC to my office iMac, which is connected to the marvelous Audio Engine 5 self-powered speakers. Of course, being who I am, the leap was conducted in slow motion. Many, many, many moons later, amidst more deadlines than I wish to recount, I began unpacking the DAC1 and appreciating all that it has to offer.
- Design: Dual Differential 24/192 DACs
- Digital Inputs: Three Coaxial, One Toslink
- Analog Outputs: One Set XLR, One Set RCA
- MFR: 20 Hz - 20 kHz, - 0.1 dB
- THD+N: 0.00056%
- Dimensions: 1.7" H x 9.5" W x 9.33" D
- Weight: 3.5 Pounds
- MSRP: $1,275 USA
- Benchmark Media
A Complete Re-evaluation
Comparing the reference system I employed for my initial DAC1 review to what I have four years later, the differences are significant. My reference transport, DAC, preamp, amplification, and power treatment have all greatly improved. I'm also using a different pair of speakers, Eggleston Works' The Nines, which will receive copious praise when I review them in a few months.
Power itself has taken a mafjor step forward thanks to a dedicated line monitored by new circuit breakers rather than an ancient fuse box. The room too has changed for the better, morphing from a 14.5' x 17' living room with a ceiling height of 8' to a much larger, far more open space that truly allows a system to shine. The only constants over the past four years are the interconnects, speaker cables, racks, brass cones, some of the pillows in room corners, and a few invaluable tweaks whose mere mention drives some folks batty. That I now also use Shakti Hallographs and the Marigo Signature 3-D mat version 2 may in fact drive my harshest critics completely over the edge. It's a shame really, because if they held it together long enough to try the DAC1 USB, they would probably stick around for the long haul.
In short, my standard of comparison is far higher than four years ago. I'm able to hear a lot more of the DAC1s strengths and weaknesses, and compare it to a far more expensive, near state-of-the art DAC/preamp. As you will soon read in detail, I liked what I heard.
Options and Features
The DAC1 comes in two models, the basic DAC1 ($975) and DAC1 USB ($1275). Save for the addition of the USB input, the two units look, sound, and measure alike. Therefore, my discussion frequently refers to the sound of the DAC1.
Three faceplates are available for the DAC1 USB: black, silver, and black rack mount. The latter has a longer faceplate with four holes in the corners for rack mounting. The top of all units is black.
The front of the DAC1 USB includes, from left to right, an input toggle switch; two HPA2™ high-current, "0-Ohm", high-output ¼" headphone outputs; and a calibrated volume control. The headphone outputs are always on, and always controlled by the front volume control unless the unit's internal jumpers are called into play.
The DAC1 USB's rear includes, from left to right, two unbalanced RCA outputs; an output level switch that toggles between "Calibrated" (near full-volume fixed output), "Off" (analog outputs are muted and headphone outputs remain active), and "Variable" (volume is adjusted by the front panel volume control); 10-turn calibration trimmer screws located to the left and right of the output level switch; two balanced outputs; four digital inputs (AES/SPDIF; AES, Toslink, and USB); and a 3-prong AC IEC connector plus a fuse drawer that holds two 5 x 20 mm 0.5 A 250 V Slo-Blo® fuses. The fuse drawer also features a voltage selector switch that can be set to either 110 or 220.
The DAC1's input accepts sample rates from 28 to 195 kHz in coaxial, XLR, and optical modes, and up to 96 kHz in USB. Maximum input word length is 24 bits. Digital input impedance is 110 Ohms on XLR input, and 75 Ohms on Coaxial input. Balanced analog output impedance is 60 Ohms, and unbalanced analog output impedance is 30 Ohms. Headphone output impedance is <0.11 Ohms.
Further stats are readily available by downloading the DAC1 USB's manual (currently in Revision C form) from the Benchmark Media website.
For use with an outboard transport, installation for the DAC1 USB is as simple as can be. Connect a digital cable from the transport to the DAC1 USB's appropriate input, then toggle the front panel input switch until the input light indicator(s) remain(s) on without blinking. Next, decide if you're using the unit solely as a DAC, or as a DAC/preamp. If using as a DAC/preamp, switch the output level switch to "variable," and connect output cables from the DAC1 USB to your amplification. If using solely as a DAC, switch the output level switch to "calibrated," connect output cables to a separate preamp and complete the chain with amplification and speakers.
Use with a USB output device is just as simple, at least when it's a Mac. (I have not tried the unit with the Windows operating system). The key to optimal sound is which versions of the Mac operating system and iTunes you're using. Because optimal configuration changes each time Apple issues with a new revision to its operating system or iTunes, checking Benchmark's online "Audio Information Center" is essential.
I will discuss my own extremely positive experience with USB set-up and playback further on in this review.