First USB DAC/Amp purchase--NuForce uDAC-3 vs. Audioengine D1

[slmckay73]

Hey everyone. 
 
I'm planning on making my first DAC/amp purchase soon, and I have it narrowed down to the two models in the title: the Audioengine D1 and the NuForce uDAC-3. Both seem like really solid pieces of equipment from everything I've read either here on Head-Fi or elsewhere, and I'm having trouble deciding between the two. The uDAC-3 is a tad cheaper, but also a little harder to find. (I think there's some sort of acquisition of NuForce by another company going on that might be affecting the availability.) The D1 has a better frequency response range, but I don't know whether or not that would matter since my headphones (ATH-M50x) have a marginally less extended range, and I'm not sure, but I would think they would bottleneck the D1. So, other than price and slightly different specs, there just doesn't seem to be much discernable difference between the two, and I couldn't find any direct comparisons by searching the forums here. Does anyone have experience with one, the other, or preferably both that could shine some light on this? Any input would be greatly appreciated. 
 
To give further context, my planned setup is a MacBook Air running iTunes with 256kbps AAC (yes, I know, I'm a scrub) and some ALAC going through one of the above DAC/amps to Audio Technica ATH-M50x. I listen to a lot of stuff that's more acoustic, i.e. folk, indie singer-songwriter, etc., along with some alt./indie rock, and a tad of pop-ish and more electronically oriented stuff like Twenty One Pilots, Owl City, and the Glitch Mob. A few favorite artists (other than those previously mentioned) are Needtobreathe, Switchfoot, Passenger, The Oh Hello's, Imagine Dragons, and Josh Garrels. 

 

[billybob_jcv]

The spec that bothers me about the D1 is the 10 ohm output impedance. The general guideline is that you want the headphone impedance to be at least 8X the amp output impedance. So, with a 10 Ohm output impedance, that means the headphones should be 80 ohms or greater to meet the guideline. That guideline was established to prevent hiss & distortion. It doesn't mean you can't use the M50 with the D1, and it also doesn't mean you definitely will get hiss, but it means you might. I would much prefer an amp with an output impedance of under 1 ohm so that problem is completely avoided.

Have you considered the Schiit Fulla?

 

[slmckay73]

Oh, I had never heard of that guideline before. I haven't seen any mention of hiss in any reviews, though I don't remember exactly what headphones/IEMs the reviewers used. I'll do some looking into that. And no, I haven't seen that one. I just looked for it on Amazon and didn't see any listings; what's the usual street price? Also, I just checked the NuForce website and it lists the uDAC-3 as being suitable for headphones from 16-300 ohms. I couldn't find and output impedance though, unless this is it: 
Headphone Output :80 mW x 2 @ 16-Ohm

 

[billybob_jcv]

Schiit is a very respected brand and sponsor here at head-fi. You would buy direct from them: http://schiit.com/products/fulla

 

[slmckay73]

That's definitely an awesome price point. How do you think it would stack up against something a little more expensive like the aforementioned NuForce?

 

[billybob_jcv]

I have not heard the Fulla, but I have heard several of the other Schiit products including the Modi, Magni, Valhalla & Bifrost. They all sounded great. I think the Schiit products are one of the best bargains in head-fi electronics. They publish ALL their specs and they are very open about the strengths & weaknesses of each of their products.

 

[slmckay73]

Thanks; I'll do some more research on their products. If I could actually find the uDAC for sale on a US website then my mind would be made up, but it's listed as available on the new Optoma NuForce website but is only available through Japanese dealers on Amazon. 

 

[billybob_jcv]

Did you see this site? http://www.audioadvisor.com/prodinfo.asp?number=NUUDAC3

 

[slmckay73]

I actually found it very shortly after posting my last reply. It's odd that it's the only site that still carries the uDAC. I think that's probably what I'll go with. Thanks for all your help; I really appreciate it.