First and foremost, this little DAP is capable of a truly incredible level of audio quality. With a little tweaking of the EQ via quality wired headphones or earbuds I am hearing details I have never heard before in tracks that I've listened to a thousand times. Not only that, but the tracks sound amazingly natural, like they were intended to be heard that way. The soundstage created is truly beautiful. I wouldn't call it neutral at all; it hearkens back to the feel of playing factory produced minidiscs in a high quality sony MD in the early 90s: suspend your superiority complex, relax and know that you are in good hands. This is a very enjoyable sound.
I 100% agree and found it interesting that your mind went directly to MD as that's exactly what I thought of when I heard the A45's signature. I have a M0 to compare and, while it has this airiness and ability to pull out some crazy detail from my tracks, there's just something about the A45 that says "listen to me...just...listen." It's not the clearest DAP out there, but it's still so much fun for listening. I haven't been tempted to take the M0 out of the house at all since my A45 showed up.
I am even liking the effect of DSEE HX on the standard 320kbps MP3 parts of my collection; this is the only other audio enhancement I'm using other than EQ settings: +3, +2, 0, +2, +2, +3
Thanks for the suggestions on EQ. I did have to tone down the top band to a +1 since it was just a little too bright on my iSine 10.
Have you considered the Nuraphone? It's a little different take on EQ (and a really bizarre design), but it saves EQ profiles that you'd make on your phone directly to the cans so you can use them on multiple devices. I don't have first-hand experience on it, but the tech looks really cool and, assuming it works as intended, might be exactly what you're looking for.If anyone has any advice around sets of headphones and earbuds which ARE capable of EQ over bluetooth with this unit I would really appreciate a heads up. I remember reading about some pairs which can bet setup via android app and will retain settings after connected to the NW-A45. I'm not really interested in full-size over ear style but would consider it if the sound is truly mind blowing.