Parts Connection Assemblage DAC-1 D/A converter kit
"And I hay-ulped!"
Gap-toothed and demented-looking, the Shake'n'Bake urchin comes to mind every time I regard the Assemblage DAC-1which I built. Like that insanely happy child-actor, my true participation was rather limited: the DAC-1 comes with a fully assembled circuit board, requiring only that the AC filter, three LEDs, three RCA jacks, and the feet be attached. Oh yeah, you also have to screw the top down and plug it in. Which brings us to a couple of key questions: Why a kit? and Why so basic a kit?
Kits may seem exotic to us now, but there was a time when you couldn't buy hi-fi equipment, and when hi-fi really was a hobby. Folks would construct their own systems, coming out of their solder-fumefilled basements only to play their reference recording of a steam locomotive, shake their heads, and trudge back downstairs to modify the circuit. As hi-fi became a consumer product, many companies continued to pay homage to its tinkerer roots by offering easily assembled kits of amplifiers, preamps, tuners, and speakers. These all tended to utilize basic circuits, and they generally sounded good and were easily modified. They were popular with folks who liked to work with their handsor whose tastes exceeded their budgetsand they were intensely gratifying to build and own.
So why did kits go away? In one sense, they never did. If you read Audio Amateur, Positive Feedback, or Speaker Builderor any of the British magazines, for that matteryou've seen ads for kits all along. Most of them, however, are designed for the very knowledgeable, electronically savvy audio hobbyist. Where are the Dyna, Heath, and other idiot-proof kits today?
They're ba-ack. Think of the Assemblage unit as a starter kitit's simple, teaches the most basic kit-building skills (reading the instructions and soldering), and can be built in less than two hours (by anybodyeven me, footnote 1). When you're done, you have a unit that looks very professional and works extremely well (footnote 2). You also have an insanely fierce pride in the D/A converter you "built."
If you build it...
Assemblage is the brand name of The Parts Connection's kit productsthe DAC-1 is just the first in a projected series of DIY components. As a preeminent source of high-quality electronic parts, tools, guides, and even tubes, The Parts Connection is in a good position to gauge the health of the builder/tinkerer market. They're also a division of Sonic Frontiers, so they ain't new to the concept of designing good-sounding stuff, either (footnote 3).
What they've accomplished with the DAC-1 is to reach out to the more passive audiophilesthose used to buying and plugging in components rather than sticking their mitts into the guts of their hi-fis. Thus, the unit is dead simple to constructbut simultaneously just begging to be modified (footnote 4). Their hope is that, once you've experienced the pleasures of constructing your own equipment, you'll be fired up for more ambitious projectssuch as the line-level tubed preamp or the single-ended triode power amp they have in the pipeline. If my experience is typical, then they're rightbring 'em on, right now!
You need only a few tools to assemble the DAC-1, but they should be good ones. You'll need a soldering iron capable of achieving 700$d Fwhich means a solder-station, not a $3.98 wand; otherwise, you'll tend to heat-stress the board or de-solder pin sockets from it before you get a good flow from the Wonder Solder provided by Assemblage. You'll also need #1 and #0 Phillips screwdrivers, needle-nose pliers (angled are best), one 12mm or ½" wrench, a pair of cutting pliers, a wire stripper (you can always substitute a hobby knife and carefully peel away the insulation, but c'moneverybody should have one of these), andthis is very importanta good ruler, preferably metal and marked in inches and centimeters. Also, I would suggest direct lighting and a padded surface to work on, 'cause Assemblage provides a pretty case, and it would be a shame to scratch it before you even build the unit. I have a roll of yard-wide rubber flooring that I lay on top of my table whenever I open a componentit's easily stored and costs me bupkis.
The manual is a joy to use: clear illustrations, both photographs and line drawings, show you what to do. Each stage is simple, well-described, and logical. I took my time, taking tremendous pride in the fact that my solder-joints were just as pretty as theirs (footnote 5). I would change only two steps in the procedure. When you solder the leads of the AC EMI/RF filter to the circuit board early in the assembly, you're left with a heavy weight dangling off your project as you turn the board over to solder the LEDs. I'd just reverse the steps: attach the LEDs, then the power filter. Additionally, when you solder the twisted pairs of Kimber Kable to the circuit board (and to the RCA jacks), the process goes faster and smoother if you've tinned the wires first; it's also then easier to feed the wires through the little holes in the board and the ground lug tab. This is the sort of thing that anyone experienced with a soldering iron would do instinctively; but this project should also teach the basics to first-timers.
Normally, it would be considered a breach of journalistic ethics to allow a reviewer to evaluate a unit that he built, but that's what the head office wanted in this casealthough they did draw the line at my referring to it as the Phillips/Assemblage DAC-1. Pride of accomplishment aside, I think it's a killer unitone that performs far, far better than its $449 price tag would indicate. I listened to it in a variety of systems, and compared it with similarly priced components as well as with DACs that are ridiculously more expensive. The DAC-1 acquitted itself well in every circumstance, although I'm not going to suggest that it handily beat all comers. Even if I did build it, it's not magic!
To compare is not to prove
I've already intimated that the DAC-1 isn't perfect. But neither are any of the other units used in this comparisonnot even Krell's $14,000 Reference 64. In fact, the Krell was perhaps the most instructive as to the DAC-1's weaknesses and strengths.
Now, only a crazy personor an audio reviewer (but I grow redundant)would compare a $449 unit to one costing thirty times as much and expect to find them competitive. In many senses, they weren't. The Krell, a two-piece unit with a power supply even more massive than the digital processor, cannot be flustered, no matter how complex a signal you throw at it. It's extremely flexible as to inputs/outputs and tape monitoring, and, of course, allows you to invert polarity.
The Assemblage, by contrast, accepts only TosLink and coaxial inputs, and doesn't offer polarity switching (which I sorely missed). Further, it can be stressed with high-amplitude, complex material to the point where it flattens the soundstage audibly. On the other hand, unlike the Krell, it allowed rhythmic drive and a sense of the melodic line to pass through remarkably uncompromised. Am I urging you Krell owners to trade down? Get real! I'm merely pointing out that the ultimate test of the DAC-1 rests upon its reproduction of music, and in at least one area it's hard to beat.
How'd it stack up against real-world competition? Mighty well, thank you. The stock Audio Alchemy DITB ($199), when used with its wall-wart power supply, lacked a bit of sweetness and detail in comparison. Adding the Audio Alchemy Power Station One power supply ($69) began to change the equation, as the DITB's authority was greatly improved. But I still preferred the sweetness of the Assemblage unit overall.
Audio Alchemy's equivalently priced DDE was another matter entirelyhere we have a real-world competitor that matched the DAC-1's strengths, while sounding nothing like it. Both units were very articulate, although the Audio Alchemy seemed a tad faster. I couldn't decide which I preferred, since each played to different strengths. While the Assemblage does offer an alluring tweak-factor for the audio experimenter, the DDE has a couple of power-regulation upgrades that you just need to plug in. You'll need to listen to both.
Footnote 1: Compare this to the approximately 50 hours it took me in 1987 to put together and calibrate Stereophile's Heath digital oscilloscope kit, where all the parts had to be soldered to the board!John Atkinson
Footnote 2: Outside North America, the Assemblage DAC-1 is sold assembled as the Sonic Frontiers TransDAC.Robert Harley
Footnote 3: I should note that the parts quality in the kit is exceptional, as you'd expect from a company built on the demand for high-quality audio jewelry.Wes Phillips
Footnote 4: Please note that altering the DAC-1 in any way voids the warranty. Assemblage has constructed it to make it a cinch to modifyICs are attached to the board via sockets, and there's lots of room to get to stuffbut they insist that if you do so, you're on your own. I suggest that you build it stock and get used to its character before changing anything. That way, they'll guarantee that it worksand they'll even finish constructing it for you, if you can't handle it.Wes Phillips
Footnote 5: No, really! Well, almost.Wes Phillips