Have been doing some direct comparisons of the 1A and 1Z, using same volume, same song, same headphones, etc. Only difference at this point is that the 1A has ~20 hours on it while the 1Z has ~80 hours (got the 1Z ~3 days before the 1A). Here's some of my early thoughts. (Note: all listening so far is SE with the Vegas - my 4.4mm to 2.5mm adapter is awaiting me at home but unfortunately I'm gone all week).
NW-WM1Z:
- Heavy! But feels so freakin' solid. Luckily I don't run around with this one pound brick in my pocket.
- The sound is an unusual combination of more analog smoothness with a good level of detail retrieval. It's hard to describe, but very easy to listen to. Very musical and engaging.
- Wider sound-stage than the 1A (and more consistent)
- Pairs really well with my Campfire Audio Vega's. The 1Z controls the Vega's with real authority. They're both power hitters and they mesh well together.
- Authoritative and well controlled bass.
- Never any distracting harshness.
- Preferred over my AK100/Mojo/CV5 stack. Finally a DAP that I can say that about! Looks like it's time to push the trusty stack off of reference duty. Also, the stack in total weighs about the same as the 1Z, so won't take that much getting used to the weight.
- Just noticed in looking at the above picture that the tone of the displays is a bit different! Not a SQ thing, but hadn't noticed the color-warmth difference.
- The included case is pretty cool, and I like having the flap that covers the screen for protection. Might want to get one like that opens like a book rather than a flip phone. Unfortunately we have very few choices here in the US, and my trip to HK has been pushed back a month (drat!).
NW-WM1A:
- Lighter! 9.4 oz versus 16.1oz! The 1A is only around 60% of the weight of the 1Z, but it really feels like half or less.
- UI and such works exactly the same (well, once it was changed the 1A from the EU limitations it came with ).
- Not as resolving in some ways, but more in others. More of a "cool" or "analytical" presentation than the 1Z, but in some ways is also a bit more veiled in some passages. I find female vocals to come across really clearly (almost too clear) but piano sounds a bit veiled.
- More of a "solid-state" sound to the 1Z's more "tube/analog-like" sound - as in analytical versus a bit warmer.
- Might pair better with different IEMs than the Vegas.
Shared thoughts on both the 1A and 1Z:
- Construction is top-notch, best I've ever seen in a DAP. Sony did it right. I love the leather on the back as it let's you set it down softly on surfaces.
- Cool to have SE and balanced outputs and not have to worry about plugging the wrong cable in (sorry LHL - it's a risk!).
- The UI is really smooth. The ~1/2-1 second delay is a bit annoying, but once you get used to it I find it not really bothering me anymore. The structure of the screens and menus and such is pretty intuitive.
- I like the 4-way swiping you can do from the "playing now" screen, as well as the four "go-to" buttons on the bottom of the touch screen. They're not really buttons, per-se, but the four selections are the same in any screen.
- The charging is really quick using my Anker 20000 mAh battery, and the battery lasts really long - well over a day in my experience with SE. Compared to my AK100/Mojo/CV5 stack this is forever.
TL;DR - For me NW-WM1Z>>NW-WM1A, although still have to burn both in and then try out the 4.4mm balanced output. Can only dream of what the 1Z will sound like with a good balanced cable and fully settled in. The 1Z displaces my AK100/Mojo/CV5 stack as my new portable reference. As such, the ~3x price difference is worth it for me, but as another hobby-member told me the other day, I'm crazy.
Cheers