Pros - Great sound, pretty neutral, extended, clear, great all round, deep insertion, replacable cables
Cons - Neutral, deep insertion, may be sibilant if not properly inserted (deep), grainy compared to high end sets, replacable cables
Summary: These require deep insertion. Once inserted they are neutral, extended and adaptable. They don't really have any sound signature that shines through recordings but instead adapts to what is being played. Great for the price. Very versatile.
I bought these used from a fellow head-fier. Coming straight from the GR07, they sounded bright, dry, flat, grainy and unrefined. However, just 2-3 songs into the audition I forgot all about them. The brain is great at getting used to small flaws. After that I just heard the great sound. They really show you what's in the music. If the music has plenty of mid bass, they play it for you, if the recording is cold and sibilant, so are they. A great iem at doing what they are told to do. At first there was one thing really bothering me, sibilance. After really pushing them in, it disappeared. I previously tried with some paper pushed between the nozzle and the tip to absorb the treble. That muddied up the mids a bit, killed the extension and increased the bass (something I think many would like actually) but for me, they lost their real pros.
I'm using them with the orange hybrid clones, a very deep insertion (for me not used to it) is required to get rid of the sibilance. The cables are a pain in the ass really but with some duct tape or similar it's fixable. Otherwise they just fall out if you're moving too much without being careful about the cord. The form factor is pretty good with small housings that feel durable. Wearing over-ear is my preference even if the ends point in an odd direction. Wearing them down produces too much noise for my taste but if I'm not moving it's fine.
NOTE: I'm just writing this a bit casually. The sound impressions are mostly from memory but I just had to listen to them to confirm. Really enjoying them.
Bass: Extended, quite flat without the bass boost or mid bass hump. Texture is quite good but lacks the "organic" (in lack of a better word, that's how I always think of it) texture and decay of the GR07. Quite fast response and good impact. No bloat unless it's in the recording. What really surprised me was the ability to produce a warmer sound with more mid bass in some live recordings where I've previously thought "hey, there's some powerful impact in the bass here".
Mids: One word "neutral". I've always had a hard time describing mids. There is a good balance between the lower mids and the higher mids. They neither sound warm, nor do they sound cold. Though they can be anything if that's what they're told. (OMG did I just rhyme?) The resolution isn't the greatest compared to higher end sets like R-50, UE900, GR07 or Re0 but like I wrote before. You get used to it and soon it's not really any problem, I don't feel that there's anything lacking there. Detailing is good. Overall mids are great.
Treble: Here's where the real issue lies. If they're properly inserted there are only hints of sibilance, mainly in the "sssssssss"-department and some cymbals. Otherwise they're fine. Not emphasized, the treble just blends in with the rest of the sound. However, if they're not inserted properly. There is some eardrum cutting sibilance with every "s". Compared to better extended sets like 2/3 blocked UE900 out of a C&C BH output 2, R-50 or Re0 they sound less airy less sparkly. However the R-50 (stock tips, don't have comply yet) and Re0 (hybrids) are more offensive in other ways in the high mids/treble.
Pros - The clarity and audio quality is incredible, the build quality is very good, and the price is AWESOME!
Cons - It might some time to get used to.
The worst part of it was the burn-in, really. You can't use them if they don't play music for 100 hours like the chinese tag on the cable says, they're too bright. But after 100 hours...
In a very short phrase, those earphones are the best you can get for this price; And if I had to describe using one word, that would be clarity.
It's not just the highs, but the mids, and the bass are CLEAR!!! They're detailed, and, unlike similarly priced earphones, you won't feel they need to be EQ'd to reduce mud in the voice. Oh, and you'll discover some new instruments in your music
What I was really surprised with was the bass though. It's very well balanced (It doesn't lack bass, but it's not too much either. No, you won't miss it!) and VERY clear like the rest of the frequency spectrum. If you do like a LOT of bass though (or a specific song sounds better with more bass), you can boost the 60-80Hz range a bit, and voila, tons of clear, undistorted bass!
I don't really have lots to say besides that you'll love those. (English is not my main language, and thus I don't know all those audio-specific terms to be able to describe them in more detail).
Just a tip; If you're 14 like me (or your ears are very small), don't try using the tiny black tips. They're too hard and will make you suffer. Use the salmon colored ones (pinkish orange). When they're inside your ear they're just as small, but much softer. It will take a while to get used to, but after that you'll love them!
Pros - Clarity Above All (more transparent than RE-400s! O.o), Price-To-Performance Defier, Big sound for small drivers, Neutral/Analytical with good bass
Cons - Detachable cable can be bothersome to some people (although I never encountered any problems with it)
Truth is, I'm speechless with the VC02s. Shocked. But I realize I have to get over from being stunned by their awesomeness to be able to describe them well and how well they really perform.
Note: This would be my first attempt to write a review as I really like them and want to share others how awesome they are!
Clarity, I think is the most notable trait they possess. There is zero sign of muddiness or any hint of any part of the frequency clouding the whole spectrum. While they do not belong to the "enhanced (bass usually)" group, you can easily hear every instrument that is present in the recording. Not only hear every instrument, but they also effortlessly render what every instrument is doing. I have lots of technical music (mostly progressive/extreme metal to be specific) that have lots of busy guitar parts in the background in my playlist that mediocre (in SQ) IEMs won't be able to handle pretty well and the VC02 just effortlessly renders them "all". They have just the enough soundstage to have room for every instrument to be heard and understood properly.
The highs are crisp and extended well, although not as I would define crystal clear like HE-400s' top-end extension, but HE-400s have a mid-high dip which makes them sound restrained or its timbre unnatrual that makes me still prefer the VC02s in terms of the overall tonal balance.
The mids are where the VC02s show its potential. They have the most honest mids I have ever heard. They almost don't have a signature for the mids unlike other IEMs where they have a certain way of reproducing mids. Say the GR06s' mids sound thick in every song, or the GR07s' mids are a little lacking for some guitar-oriented songs. The VC02s' mids totally depend on how a song is recorded. At first I thought they have a bit forwarded mids that guitar parts on RATM songs sound throaty and tubey which is very nice. Then I listened to The Haarp Machine and the mids were more flat instead of slightly emphasized. And then on Soilwork's album Stabbing The Drama, the mids were slightly airy and kinda soft. For my other IEMs those changes from different recordings do not seem that obvious to the extent that it may fool you to think that the way mids sound on a certain recording is the sound signature of the IEM itself.
The bass is tight and punchy and has enough weight for the songs that require it. Again, these do not belong to the "bass-enhanced" group, so bassheads that want unreasonable amount of bass, look elsewhere. The bass somewhat shares its mids characteristic in terms of versatility. It can be very fast and tight where very fast double bass drum strokes on The Faceless' album Akeldama are cleanly reproduced. But on Soilwork's The Panic Broadcast, the bass drum is more like big and slightly bloated instead of tight and clean.
To those who won't appreciate these IEMs at first, I suggest you give it some time to realize how good it is technically. With the VC02s I have effortlessly heard parts of songs that I've been giving a lot of effort to hear. I really can't get over that I bought these with their MSRP of $40 (about $37 actually). To those who love neutral, don't look back! Vsonic really defies priceerformance ratio with these VC02s. This is a must-have for all audio enthusiasts.