Pros: Natural Sound, Great Bass.
Cons: Too much bass when paired with wrong equipment
I will start this review by providing some background. I had just purchased a Beyerdynamic T1. I paired with a Bottlehead Crack I loaned off a friend and it sounded amazing except for one thing. There was too much treble energy and it hurt my ears. I tried burning it in and it only improved slightly. The other problem was a clear lack of bass impact. There was some midbass hit but low bass presence and body was severely lacking. I decided that the Beyerdynamic T1 was not for me and sold it.
Shortly after, I read a review on Headfonia that claimed that this Neko DAC (which I had never heard of) was a fantastic natural sounding unit with plenty of low end emphasis. It sounded like the perfect solution for the T1! It was a pity I read it after selling the T1. Anyway as fate would have it, I found a refurbished Neko unit for a fantastic price. I bought it without hesitation and then began rebuilding my set up. I was more careful this time and I actually bought another T1 and had it recabled by Whiplash Audio with their latest and greatest Hybrid V3 cable.
I had a Burson Soloist Amp at this time and I figured that since it did such a great job with my MrSpeakers Mad Dog 3.2 that it should be able to handle the now re-cabled T1 and the bassy Neko DAC. Unfortunately the Soloist has a very strong character of its own that it imparts regardless of DAC used. When I plugged in my T1 to this new setup, all I heard was the Burson Soloist. I switched out a few DACs and it was still the same. I decided to go back to the trusty Bottlehead Crack that my friend had and pair it with the Neko. What I heard was MAGIC. THIS was THE sound. 3D, wide, smooth, detailed, full-bodied, spacious, clearly imaged. Sparkle, yet with all the bass impact/body I wanted. I lacked nothing.
I of course then proceeded to buy my own Bottlehead Crack amp (had it upgraded with a better stepped attenuator and capacitors - thanks @Loquah), added an Audiophilleo 2 to increase detail retrieval and perfection got even better.
I'll come back to the Neko now and not make this a T1/Bottlehead Crack review. The point I was trying to make though was that equipment synergy is of utmost importance.
Pairing the Neko with a Burson Soloist did not yield the results I wanted with the T1, but it worked well with MrSpeakers Mad Dog 3.2.
When pairing the Crack with Neko and Fostex TH900, the sound was overly dominated by bass elements in the music. It sounded great but it was very imbalanced.
Burson Soloist with Neko and TH900 resulted in a weird unnatural disjointed sound that had bass impact that hit unnaturally hard, too much treble emphasis and everything else was not present enough. However, I found that it was mainly the fault of the Soloist as no DAC could make it work well with the TH900.
Even the mighty Bakoon HPA21 + Neko + TH900 resulted in music that was noticeably tilted towards the bassy end of the spectrum.
The only amp that could make the TH900 work with the Neko was strangely enough the RSA Intruder which is a very good and very neutral portable amp. That combo was strangely potent.
Anyway, this DAC has very unique qualities and anyone who has a good transparent amp and equipment they wish to inject a massive dose of natural bass-laden sound to neutralize over-excited treble, this is the DAC for you. Just make sure your headphones are good enough to bring out the best from the Neko and that your amp does not color the sound so much that the Neko cannot shine through.
I cannot recommend the re-cabled T1 + Crack + Neko combo enough. It's very special.