Unreasonable? It means not being guided by or being based on good sense. Synonyms include uncooperative, obstructive, unhelpful, disobliging, unaccommodating, troublesome, awkward, contrary, difficult, tiresome, annoying, vexatious. Want more? Obstinate, obdurate, wilful, headstrong, pig-headed, bull-headed, intractable, intransigent, inflexible, mullish. Still more? Let's add irrational, illogical, opinionated, biased, prejudiced, intolerant, blinkered, unacceptable, preposterous, outrageous, ludicrous, absurd, senseless, nonsensical, irrational, illogical, excessive, immoderate, extreme, disproportionate, undue, inordinate, exorbitant, extortionate, extravagant, intolerable, unconscionable, unnecessary, unjustified, unwarranted or uncalled for. Phew. Who actually still uses vexatious?

The trouble with synonyms is that often, they aren't; exactly. The above list expresses quite the range. If I now tell you that the D2 did perform unreasonably close to the D1, not all those synonyms fit. Once you've read my brief comparative take, pick from these options what you think most appropriate. I have my own favourites. Sonically cut from the same cloth with that very high super-fine thread count of top resolution and great though never bright illumination, the key difference occurred in the lower half of the bandwidth. Here the D1 played it a bit heavier yet also bloomier. If this was linear versus switching power in action where I have no way of knowing, the traditional solution created a bit more warmth or fullness. This came at the expense of ultimate control. The SMPS had the tighter grip or higher damping. That came at the expense of ultimate weight. But "at the expense of" only meant a small shift; no major transaction at all. In fact it wasn't sufficient to cause the usual effect whereby, whenever the lower half of the bandwidth gains a small emphasis or textural change, the upper half seems to do the opposite; or vice versa. That game would be louder. Not here. These hardware swaps caused no real teeter totter. Thus the upper half of the bandwidth really stayed put; unaltered. The small pendulum hinged in the lower midrange. Like a grandfather clock, there it ticked back and forth for a small shuffle between the values already explained. And just like the chosen imagery, I'd call that mostly a sideways not vertical movement. I said mostly because that determination depends on your preference and hardware. If those need some extra weighting below the belt line, you'll consider the D1 a slight move up. Conversely, the love handles of bloomy ringy speaker ports would benefit more from the D2's somewhat firmer slightly leaner demeanour. Finally, if your system and ears were happy either way, you'd call this no more than immaterial wiggle room.

Pig-headed? Thinking about Fang Zhiquiang aka CC, sonic sifu and clear obsessive, I wondered. Had he forced his compatriots to push the little D2 far too close to their big flagship? So what if it lacked the latter's RCA/XLR analog inputs? Most modern users no longer have need of them. So what if its max output voltage is far eclipsed by the D1? Which modern amplifier's input sensitivity falls below its own 4 volts? And who will need two coaxial inputs? Personally I prefer the D2's AES/EBU which the D1 doesn't have. Go ahead then. Scroll back up. Revisit our unreasonable synonyms. In just this context of direct sibling rivalry, might extravagant be justified to describe the D2's achievement?

In the bigger context beyond the brand, €3'900 with volume control and remote obviously remains still quite the number. Cynics might even say that the D2 is what the D1 should have been all along. But no matter which side you come down on, finding a machine that is as sharply dressed as this clean-edged Taiwanese; that is as carefully featured to even think of that defeatable buffer for video lip sync and defeatable USB 2.0 for driverless WIndows; that is as purposeful about preamplifier use with a quality analog attenuator of 0.25dB steps yet which makes that a €700 easy retrofit option so buyers with already serious preamps won't pay for redundancy... finding such a direct competitor won't be so easy. And yes, direct drive's ultimate success will rely on you being completely content with how your amp/speaker combo dovetails. The D2 won't add any real seasoning to it like one might pursue with a valve preamp or very high-current transistor unit to increase dynamics or fill out tone.

The D2 presupposes that its source and volume control duties should focus on neutrality and resolving power but should manage those tasks not with just clinical expedience but demonstrable elegance. Admittedly elegance is a dificult word to assign as an audio quality. Again I return to a truly superior tweeter. It aces elegance by what it doesn't do. Yet its telltale reveal of airiness and luminosity still touches everything else. That's very much also the action of the D2. Whilst I've never heard folks complain of too many transistors, I routinely see tube lovers caution against too much glass. According to their beliefs, a tube DAC plus tube preamp plus paired tube amps gets excessive and sonically counterproductive. Enter the D2 in either DAC or DAC/pre guise. It'll take out one or two of these tube components like Timothy Olyphant's laconic federal marshal Raylan Givens does it: looking and sounding cool. Especially lovers of direct-heated SET who, most carefully and often involving costly trial and error, have set for themselves a very particular valve aroma could really find the light-filled sophisticated D2 ideal. If I didn't already own the D1, I'd be most tempted to keep the D2 as a one-box DAC/pre. In fact I quite prefer its display, digital XLR and more easily set volume controller. I'm positive you'll do the rest of today's math. Now what's your favourite synonym for unreasonable?

COS Engineering website