TL;DR version:
I bought W2-131 and wondering if I should try W2 next. Want a bit closer female vocal, a bit more treble, a bit wider, and bit more splashy cymbal / snare drum. Slightly less mid bass. Overall a tiny bit more aggressive.
Long version:
So I've had my W2-131 for almost a week now. Might need a bit more time but I want to share my first impression. My original plan was to buy PEE51 / RU6 / W2-131 to de-throne my all time favourite Dragonfly Red (most of you will stop reading now LOL, like I can't take this guy seriously).
If you're still with me here this is where I am at. First impression is that PEE51 is impressive, tons of layering and details, probably the most detailed out of all of them (my friend says might just because it's tuned treble heavy). But I can't feel it sounds "dry"? Like I'm impressed by all the detail and layering but somehow it sounds boring? Maybe it's lacking warmth, which is weird because it's regarded as one of the most "euphoric" dongle which I agree (mainly why I bought it) but somehow it still sounds "dry" I can't explain. But anyway that's out now, will sell it later.
Next in line was RU6 which I had high hopes for. It also sounded very good off the bat and here I was thinking maybe this is the one!!! But as I listen to it more and more I start to notice more flaws, uhhh or I guess preference differences. It's missing that "surrounded by violin" type of sound that W2 and W2-131 has. So I guess RU6 has a dip somewhere in the mids? And the bass seems impressive at first but the most I listen to it the more it feels it's "rounded" off and sub bass roll off. Like the hits is soft? Can't explain. Also somewhere in the treble seems to roll off again I wish I'm better at identifying frequencies but oh well this is where I'm at LOL. Low gain I notice everything is much closed in which is good because I like intimate vocal, but then it also lacks sound stage, when I used high gain it improves sound stage but then vocal too distant. After trying every option under the sun (high gain / low gain / no oversample / oversample / set my computer to all kinds of sample rates) at the end I decide to give up. Will list RU6 in the classified later also.
So here is where I'm at, W2-131 actually has the most rounded sound. Initially was a bit boring but it's slowly growing on me. Like it does everything well but nothing really "wow" me yet. It has the least interesting female vocal so far (maybe too far in the background). But surprisingly it actually has the most extended bass out of all the dongles I tried. Just wish female vocal is a bit more pronounced. I think W2-131 has a really "inoffensive" smooth sound. If I were to nitpick I'd say I wish there is a tiny bit more treble, closer female vocal, and a little bit more aggressive snare drum / cymbal, and a little bit wider.
This bring me to the point that........ should I have gotten W2 instead of W2-131? Originally I went with W2-131 because I like intimate vocal and bass, but then maybe it went too far so now I wish there is more treble and a tiny bit less mid bass. As for aggressive sound for rock........ is it just how W2 is? Smooth and relaxing kind of sound? Should I bother with W2 or try something else entirely?
Was looking at Ovidius B1 but the proprietary 2.5 mm to USB C thing bugs me, also apparently it's too powerful so you'll have hiss if used on sensitive IEM / headphone. I have 24 ohm headphone so I strongly suspect this will be an issue.
Oh for those are wondering, no it's not a landslide win over Dragonfly Red LOL. In fact it's still more "different" now than it is "better". Dragonfly Red wins in some regards (intimate vocal) but lose out in resolution slightly (not as big as people might think). Like I'm literally splitting hair over the past week A/B all 4 dongles (though mostly on W2-131). But now I'm thinking to sell PEE51 and RU6 and maybe buy / trade for W2, or something else entirely different.