Like the D3, the D1 has more than enough juice push headphones like the 600Ω DT880 to too-loud levels. It’s RCA jacks power 2VRMS, which is perfect for most amps and speakers. Like the D3, it powers my new favorite, Dan Clark’s Alpha Dog, with verve. It does its job.
Unlike the D3, it boasts an on-board volume pot which makes fine-tuning volume much, much easier. Because its gain is aggressive, when listening to earphones, I tend to keep iTunes or Audirvana at about half volume. That lets me work with about 15% of the volume pot via the Ultrasone IQ. With low-current voltage-hungry phones like the DT880, I have endless pot to play with.
Not bad, but better does exist. Really, I would love for it:
1. to have a user-selectable gain
2. to have a lower initial gain
Like the D3, its power is backed by good, but not perfect current into low-Ω loads. The sweet spot is the portable headphone and the earphone that isn’t overly current-hungry. Here are its accolades:
Aberration-free frequency response and stereo signals
Amelioration of signal noise
Super-sensitive earphones like the Ultrasone IQ are practically hiss-free. Your 2500$ AK240 won’t do better. You can be sure that pretty much any other earphone will be hiss free. Its lack of hiss gives freedom for the midrange and upper frequencies to express detail.
The D1 supplies most earphones with enough current at any voltage level. Even when driving earphones whose impedance fluctuates wildly, the D1 drives a decent signal, with only minimal aberration. The majority of those aberrations reside in the stereo signal, which takes the biggest hit. Still, it is minimal. And I am firm in my belief that the D1’s DAC is what holds it back in absolute performance. And I am firm in my belief that AudioEngine chose the D1’s DAC to express their vision of sound.
It is a warm, smooth, and semi-detailed sound that goes great with everything but fast trance, large orchestras, and some dubstep. More on it below.
I was impressed by the D3. The D1 is better. It hisses less, and else-wise, performs very similarly. That means that many of the caveats that applied to the D3 apply to the D1. Of course, the D1 has been around for four years. And for the majority of that time, very little has changed.
Nothing really need change.
What I said in the D3 review applies:
That’s all to say that if you’re a Dubstep fan, and your favorite headphones are the Grado GR10 (imagine that), you will miss a bit of the deep bass groan you crave. But plug in any headphone and Whoomp! There It Is.
The D3’s amp delivers unimpeded stereo separation and signals integrity to most earphones. Again, low-Ω earphone owners may notice the odd uptick in upper mids, and the slight loss of bass detail, but that loss is minimal. Overall, the diminutive D3 delivers a good, if not excellent listening experience to pretty much every earphone out there. In no way does it impede the performance of the DAC.
One thing to note: while the Alpha Dog gets loud, and sounds pretty good through the D3, there are slightly better ways to enjoy it. Still, the D3 is a good upgrade to every computer on-board headphone amp I have heard, bar none. If it’s an upgrade to your on-board that you’re Jonsing for, the D3 packs a punch.
NOTE: this part, too, reads very similarly to my earlier review of the D3.
Besides power, D1 has a very decent DAC interface. First, everything just runs. If you use OSX, there are no settings to change. If you have the right application at your disposal (I use both Audirvana and iTunes in OSX), DSD files perfectly sample via DSD over PCM. The D1’s DAC down-samples rates of up to 192kHz to its native 96kHz for hiccup-free playback.
The sound the AK4396 DAC produces is a mix of smooth, of mid-driven, and of smoothly rolled highs. Most of its definition huddles in the upper mids and bass. Highs are smoothed out more than is typical for a device in the price range, which is a nice change. There is in fact a noticeable treble roll off that finishes just shy of 20kHz. That roll off smooths out brash elements. It also makes the mids stand out a bit more.
Contrast is mid-centric, giving the D1 a laid-back signature. Stereo image, too, is laid back. Actual stereo separation falls into the measurable distance typical of good valve amps. Because so much of the signal prefers the midrange, detail, and separation within mids, is natural, especially for headphone use. There’s no way poorly-recorded albums will make you as dizzy through the D1 as they do from other, contrastier devices.
Transitions within all spectra are smooth. Again, they lead toward an expressive mid section and a powerful bass. Stereo imaging is like a big balloon just around your head. Many of the cues come from the left and right, and filter toward the middle, where atmospheric cues fill in the details. You won’t be picking out the smallest of stereo details through it, but you’ll get a prettier picture of what’s going on. Holistic, not atomistic.
That’s to say that the D1 is probably a better match for progressive rock, and jazz, and folk, than it is for trance and industrial dubstep. Experiments from The Alan Parsons Project, in particular I Robot, really do deserve the mellowing, beautifying touch the D1 gives.
The D1 is basically a bigger, badder D3. It has the same basic sound signature, but pushes less noise into the signal. Its chassis is pretty meh. What I love is its solidly-cored RCA output. That it also boasts optical in is pretty rad. Oh, and a volume pot. Honestly, I can’t believe that it goes for 169$. Not at all. Its amp is strong and high quality. Its DAC, while not reference-quality, gives your music a nice laid-back touch. It feels great.
I even dig the fact that I don’t have to do a reacharound to get the D1 connected to the D3. I like that very much. But the D1’s soft-touch front and back look and feel cheap, but the D1 really is the genuine McCoy. If you’re into the laid-back AudioEngine sound and have 169$ laying around, you can’t really go wrong. Honestly, the D1 is one of, if not the best buy out there for its asking price.