Hi,
I bought NX1 of ebay some time ago after reading good opinion about it. I wanted to find out how does it compare with my old Little Dot MkI+ which has more power, but is also quite old and noisy. In general I wasn't disappointed. It is not a superstar, but it definitely punch above it’s price. However, it lacks a bit to compete with Little Dot with more demanding cans (like HD650).
Background noise of NX1 is an issue with sensitive IEMs, even on low gain it is on the level which is barely acceptable and high gain is unacceptable for music with quieter sections, this is similar to Little Dot. My impressions in different setups below.
Size comparison with Clip+, iPod Classic and Fiio X5:
With Sansa Clip+ and Custom Art Music Two
This setup didn’t yield great results for most of my test music. The biggest issue was rather siblant highs, which sounded smoother straight out of Clip+. Mids became a bit “plastic” sounding. I’m not going to use NX1 in this setup as I prefer M2 straight out of Clip+
With iPod Classic (7th gen, 2009) and JH Audio Roxanne
iPod HP sounds warm in comparison. NX1 mids are slightly recessed or is it a slight lower mids bump in iPod. NX1 soundstage seems to be improved, definitely more depth. However, I’m not going to use this setup due to background noise.
With iPod Classic (7th gen, 2009) and Sennheiser IE8
Nice improvement over iPod’s HP out: sound gets more 3d and slightly wider, much better separation of instruments and more accurate placement. Slightly recessed mids adds to more enveloping feeling of the music. IE8 are not that sensitive, so the his is not an issue on Low gain. On high gain it was audible, but low enough not to bother me. In general this is my favorite setup of NX1 so far. I actually had a magic moment, when I was comparing Music Two with HF5 and IE8. I switched to IE8 and I just stop comparing anymore, just listened for the full album it was so good.
With iPod Classic (7th gen, 2009) and HD650 (vs Little Dot mkI+)
First of all I was actually surprised how good iPod’s headphone out was with HD650 (I think it was the first time I tried it in this setup). NX1 (on H gain) added little bit of dynamism and improved highs and bass response. I wouldn’t call it ‘synergy’, but definitely listenable set-up - I like what NX1 did to highs here, making them crisper, but it still sounds a bit veiled (which is attributed to HD650).
Replacing NX1 with Little Dot mkI+ provided bigger improvements: more dynamic sound, better soundstage with better instrument separation, more forward mids, but it also retained a crispness in highs. Bass is tad more impactful with Little Dot. In general, more musical and involving sound.
In this setup Little Dot mkI+ wins, but it is probably 3 times bigger and 5 times more expensive and has 1/5th of battery life.
I also did a short test with HiFIMan HE-400 which I think were driven by this amp acceptably well, but I didn’t have time for proper comparisons.
I also paired it for a quick test with Fiio X5 (via line out) and Roxannes. NX1 slightly boosted highs and lows, but background noise was too annoying in this case (wouldn’t be an issue with less sensitive headphones).
Conclusion
When you consider NX1, you need to keep in mind it’s low price. It can’t compete with much more expensive amps, but for very little price it can improve many setups, esp. with full size cans. I wouldn't recommend it for sensitive IEMs, but for anything else, on a budget, definitely recommended.
Let me know if you want to know my opinion on it in any other gear combination I have - I can do more testing when I have some time.
(I forgot to take a picture with Little Dot for size comparison
)
