At the other end of the spectrum, the uDAC-2 can impart a very slight edge on some treble transients. I spent a lot of time on this point because, quite frankly, Redbook CDs (most digital music) tend to be recorded with a slight edge (pre-ringing) on some treble transients, making it tough to know whether any edginess you might hear is attributable to the recording or intrinsic to the device under test. What I want to suggest is that the uDAC-2 performs in an exemplary fashion here, doing almost nothing to make the problem of treble edginess worse, but also not fuzzing up or blurring treble transients in an effort to filter away problems inherent in the signal. That said, on occasion I felt that the uDAC-2 was just a little bit thrown off by these difficult treble transients. But to put this comment in context, let me observe that almost every DAC I’ve heard below the $5000 level has at least some issues with handling fast-rising, high-energy treble transients and some DACs certainly are more upset than the uDAC-2 is when the going gets tough.
So as to avoid confusion, let me emphasize that I didn’t think the uDAC-2’s treble response sounded overly bright. In fact, I’d rate the uDAC highly for a neutral treble balance overall.
The big deal about the uDAC-2 extends directly from this even-handed approach to treble frequencies. The beauty of the uDAC-2 is its blend of clarity and instrumental separation. Each instrument sounds clear, yet not in a forced, painful, or artificial way. Instead, the uDAC-2’s clarity is the real deal, especially when you stop to think about how live music actually sounds. You can hear each member of a band quite distinctly and you hear the details of their instruments even as they decay to low levels. Once you’ve heard delineation like this, you start to notice the smeared, slightly foggy sound of other competing products.
Related to this, the uDAC-2 also does a fine job of following instrumental transients as they gradually decay toward silence. This, as I’ve pointed out before, is very helpful in establishing a realistic and flowing sense of ambience on many types of recordings, and especially on orchestral pieces.
On The Unthanks’ song “Because He Was a Bonny Lad” from Here’s The Tender Coming [Rough Trade], the opening voices decay impressively in a natural acoustic environment because, with the uDAC-2 in play, the very low level reverberation within the recording venue can be clearly heard. The voices of these sisters are nicely delineated, and the overall shape of the sound is full.
The guitar and rhythm section on Shelby Lynne’s “I Cry Every Day” [Suit Yourself, Capitol] show off the dynamics of the uDAC-2. The acoustic guitar is naturally showcased, though the lower midrange might be just a touch soft. The uDAC-2 has a musical way of handling dynamics in contrast with some other devices, which might sound punchier at first, but ultimately wear on you by sounding artificially amped up.
On “Young Blood” from Norah Jones’ The Fall [Blue Note], the electric bass has good string definition and weight, though I had the impression that some slight bit of air was missing. The vocal sounds clear, refined and has good body.
A key aspect of the uDAC-2 is that the headphone amp has plenty of power, viewed from the perspective of micro-sized amps. NuForce is managing a delicate balance here, since the mobile nature of the uDAC-2 means that more likely than not users will have relatively efficient earbuds or heaphones. At the same time, some users may want to buy the uDAC-2 so that they can bring along difficult to drive full-size ‘phones. The uDAC-2 was adequate with the Sennheiser HD 800s, which I would consider moderately difficult to drive. Other more efficient headphones could be brought to brain-crush level with ease. That said, some difficult-to-drive Beyerdynamic or HiFiMAN ‘phones may stretch the uDAC-2 too far, but I did not have those headphones on hand so I can’t say for sure. As always, try before you buy.
Another compatibility aspect of the uDAC-2 is the way it fits on a desk. Yes, it is small, but it is so small that the USB cable and headphone cable you use will almost certainly tug on the uDAC-2’s chassis and cause it to move around. I’d consider Velcro to mount the uDAC-2 securely, particularly if you use it in the vertical orientation suggested by NuForce.