Recently received this little dude via Canada from Japan: it's a headphone conditioner that cleans up all interference from electrical or wireless signals. It's from Japan and is essentially not made in this model any more.
It can run single ended or balanced, and it's interchangeable, so you can run single-ended to balanced, vice versa, or balanced to balanced, or single ended to single ended --- it doesn't matter. I am waiting on a balanced cable to be made so I can run my 2A Sig balanced to balanced.
The wire that comes with it (shown in blue/white) is crap. The plug is too short and it doesn't "click" into place when plugging into my equipment. I had to use another cable with a longer, more standard plug. The black one is a Cardas cable I got from Amazon for 14 bucks or so.
I've been running my Geek Out 2A Signature into it, as well as my LG V20 and I gotta say, I'm very impressed so far. I ran my V20 single ended into the NIP, and then ran it out as balanced to my V-Moda M-100 for fun.
So, impressions over the NIP running from my V20:
The sound thickens pretty substantially from the NIP. Vocals are enhanced and pushed forward. More weight and punch to the music (especially drums). The sound smoothens out. The volume increases as well by a fair amount. Not really noticing much of a soundstage difference. Everything sounds a bit cleaner. Seems to drive the headphones a bit better. Everything sounds warmer. Some of these are pretty drastic changes, some are less drastic, but all of them are noticeable.