I might be the only one with both A12 and U12, have had the custom for close to a year and frankly although admitting its technical ability it never became a love story mainly because I am not getting enough bass,not until I press them in, but as soon as I let go, bass is there,just not satisfying enough, sound sig becomes more bright orientated, there's something slightly unpleasant about the treble.
Well, guess what, U12 arrived yesterday and it sounds like a different iem altogether, I really didn't expect that at all, was even thinking I was gonna sell the U version.if I didn't know what I was listening to id say it was a completely different iem.
There's bass, so much its a darker signature, treble needs yet to come out tho details are all there. I am very very fond of this iem now.
I will be contacting Vitaliy soon to send my custom back for a refit.
In a way, the custom is more detailed, but it has almost no bass in comparison and it just doesn't sound coherent, treble has a somewhat sibilant quality, tho still very detailed, just not a pleasurable listen, more just technical power that doesn't deliver almost any musical joy.
The U12 on the other hand is a completely coherent, id say like a one dynamic driver kinda sound, if anything very close to Sony Z5, more open and capable in any regard tho. I am truly shocked of the difference.I love the U,tho it needs a lot of burn in, it feels it can open a lot more, it just is a very musical,warm sound that I like and enjoy tremendously already.
If i did a blind test I would have said one is obviously a multidriver,however capable,just no joy there.the U I would say was a dynamic driver hybrid maybe,best I've heard.
My Solar is also a beautifully made, stunning sounding iem that just hasn't got anything to complain about,its bass is awesome, treble is prominent but silky and highly detailed, mids are there,but less upfront, U12 has better voice handling,very sweet, Solar is brighter yet super balanced and bassy too,tho U12 goes lower and more, difference might be due mostly tips and that very extended nozzle that gets in perfectly. U12 is warmer,lush,but highly detailed, very quiet background with mojo btw,details come out of nowhere,the effect is amazing.
Solar sounds less warm next to U12,treble comes out quite a bit more,but its a shimmering, sweet never fatiguing one, kinda reminiscent of K10 from my memories.its by no means a treble kinda iem tho, bass is also prominent, perhaps it has a slight U shape sound signature that is a lot of fun. I wish I had more than 2 ears to listen to both