NOTE
This review has been revised, but I felt it better to retain the initial impressions. which you find below. The revised review is found later.
INITIAL REVIEW
Must have spent over 30 minutes writing a prior review, then my web browser crashed! Must form the habit of preparing these reviews in a word processor, or text editor, cos that's a huge loss of effort. Clearly one improvement that needs to be made on Head-Fi.org, is autosaving. I'm familiar with other web forums which have this feature, as standard.
So this will be really brief.
The OUTSTANDING :
Build quality, looks great, excellent fit in the ear, very good selection of eartips for the price, albeit I do not use the tips, cos I prefer Clarion TRI eartips, and that's what I tested them with. The Clarion TRI is more open in the bass and the treble, especially in the higher frequencies, cos of a wider bore.
The price is incredible. you get a lot for the money. It is free from any immediately audible sonic anomalies, until you compare it to better. So its better than some of the KZ products, like the KZ ZVX, or EDC Pro., from a sonic perspective.
THE ORDINARY :
The cable is ok, nothing special. Careful, if you snag it, it may snap. A bit thin. But its a detachable cable, which at this price, is a bonus.
It's ok, sound wise, just ok, until you listen to something better, like the ARTTI T10, which is in a completely different league. The Zero 2 sounds very ordinary and with far less insight into the audio, in comparison.
Only reason to get a Zero 2, is to finally deal with your own FOMO (Fear of Missing Out), and hear what all the hype is about. For me this was a lesson, do not trust most reviewers out there, cos if this is what they say is good, and in one case someone said they were selling a Dan Clarke for this, makes you wonder how divergent human hearing can be.
The Zero 2 is worth buying as a keepsake, as a budget reference of where ACCEPTABLE starts from, but once you have heard anything better, like me, you will NOT go back to the Zero 2. It will be in the drawer living a good and permanent retirement, and you will have been cured of hypermania, once and for all.
The fact that it measures well, has low distortion, does not translate to the quality of what I heard. I was dissappointed, cos I expected more, after reading many other reviews.
Unfortunately an IEM is not a showpiece, it has to sound good, and in this case it's just OK. Look elsewhere, if you seek discerning resolution, soundstage, depth or height., or realism.
THE BAD
The plug end that terminates in a 3.5mm unbalanced (single ended) plug is thin, and difficult to hold onto with slippery surfaces and zero grip, when inserting, or removing this cable.
You do not get a case, but at this price, you should NOT expect one.
CONCLUSION :
This has cured me of any further attempt to find diamonds in the rough, in the sub $25 price bracket. Just give up, there is nothing spectacular in that price range. If it sounded great, they would not sell it so cheap. Makes sense, that one does get what one pays for, at this end of the price range. I will NOT be buying any more budget IEM's for whatever reason. Just not worth the diminished sound quality, when one has heard better, like the ARTTI T10.
TEST ENVIRONMENT : TempoTec Sonata BHD, listening to Youtube, and Spotify and high quality recorded audio, in a professional music/audio studio. I'm a working audio engineer, who makes a living from this, by day., and a live events audio engineer volunteer, at the church I attend, at the weekend.
CLARIFICATION ON COMMENTS ON THE SONICS
1. The Zero 2 lacked what I would call extension. Compared to the T10, it sounds congested, as if one has applied low pass and high pass filters, at the both ends of the frequency spectrum. The sub lows are missing, and the real highs are also missing. Worse still, no amount of EQ, can correct these problems, so its more than just frequency response.
The way I can describe it is that the attack and decay of sounds on the Zero 2 are slow, lacking a certain snap and immediacy. Bass instruments, in fact anything one hears, is NOT as defined. Placement is just not as crystal clear. In the T10, I can place everything, in the audio, in the stereo field, which is wide, ultra wide, so there is an incredible separation, between stereo panned instruments,, as well as depth - i.e how distant a source is, in the virtual space. And also how wide a source is, i.e how much of an angle from left to right does a stereo instrument such as a piano occupy. is just so much better on the T10.
2. The Zero 2 lacked the kind of clarity I hear on the T10, where I do not have to struggle in any way to hear exactly what is being said or sung. And with the T10, I can listen at very low volumes, and still hear everything very clearly.
3. It did not resolve audio as naturally as the T10, i.e its dynamic range was limited, while the T10 sounds more like the instruments and voices, are right there in the room or in my head.
I think in summary there are diminishing returns in both directions of cost. Most likely above a certain price, one is not getting much more. But also below a certain price, the savings are just not worth it, cos the value that is lost is not worth the money saved. I may be bold to say, I wish everyone could own something like the T10, and for the 1st time, truly hear what good audio sounds like.
I am glad I bought the Zero 2, and also glad I did not spend too much to buy it, but in all sincerity, people should not bother, unless they just want a reference of how comparatively bad things can get at the budget end of the IEM single DD segment.
If one has not heard the better product like the T10, which has so impressed me, one would think the Zero 2 is good. It is certainly better than the KZ products I have bought - CCA Polaris, KZ ZVX, CCA CRA (2023 revision), and the KZ EDC Pro. Definitely better than these. But its a progression. When I heard the CCA CRA, I was happy, cos it was better than the Apple Earpods which I also own, until I heard the ZVX, then heard the KZ EDC Pro which is better, then I bought the T10, and I am now in heaven, with a huge difference in realism, detail, clarity and just amazing listening pleasure. Finally I can hear what the music should have sounded like. As if I was being given chalk to eat, in the past as food, and finally discovered the taste of good cooked well prepared food, with the T10.
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REVISED - 27th December 2024.
If you read all of the above, please ignore. I did a pretty extensive comparison, and discovered that like a lying mirror, the T10 sadly was lying to me, giving me an exaggerated image of the music. In comparison, the Zero 2 is definitely much more accurate.
While a lot of people talk about frequency response, I am convinced that far more important is timing, getting a cohesive timing. I felt that the T10 upon critical listening, was smearing the audio, adding a false skin, which at 1st appears like an enhancement, but is actually a false image, and in my opinion, I would call that distortion. Either it is distortion from the driver itself, or a mismatch between the left and right driver, giving the effect of a chorus, with slight deviation, creating a composite image that is not pin sharp. like sound which is out of focus. More difficult is the T10 to pinpoint direction, which is easier on the Zero 2.
I think the Zero 2, is a balanced IEM, with enough resolution to appreciate the details of whatever you listen to. I do not know if it is the most resolving IEM in the world. But you cannot go wrong with the Zero 2, for the price it is definitely value for money. It may not be as effusive as the Zero 2, but it is definitely the more accurate, if not the most immediately fantastic sounding. If the music is great, you will hear it, and if there were any compromises made, or artistic liberties taken in the mixing, that you will hear distinctly in the Zero 2. I find it an analytical IEM and a truthful one which does NOT exaggerate. Balanced.
I definitely recommend. Guess it takes a while to learn these things. But I am glad I have the humility to admit, I got it wrong, and correct that. No contest, the $20 Zero 2 sounds definitely more accurate than the $50+ T10. This has made me rethink the hype of Planar Magnetics., unless maybe it was my own copy of the T10 which was faulty. I Think there is some kind of resonance in the planar magnetic technology, and for now will be avoiding. I almost spent a lot of money to get the S12 2024 edition. So glad I did not. Just demonstrates that there is a lot of hype out there, and the best of reviewers, and that includes me, can be misled, by the artificial coating that the T10 adds to everything. Initially impressive sounding, but its not actually better, just a smear, that loses the focus and blurs the sonics.
I do not use the stock tips. For me the TRI Clarion's fit me best, and I use these with all my IEMs.
REVISED 5th January 2025.
I no longer use the TRI Clarions, but prefer the STOCK RED eartips, that were included with the Zero 2's.
I found out that the TRI Clarions, smoothed out the sound of any IEM, taming the bass and the highest frequencies, focussing on the mids, which subjectively sounds better, but is not always so.
The TRI Clarions had skewed my impressions of the T10, and once I went back to the T10 stock tips, the contest was over. T10 is way more natural, on human voices than the Zero 2, which tells me - it is the more accurate presentation.
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Also its so hard to judge what someone else heard, cos insertion depth also plays a huge part. Everyone will insert to a different depth, and that changes the Frequency response. I now think it should be compulsory especially for those starting out, to rapidly learn the import of eartips, and eartip rolling, and 3rd party eartips, to opimize the sound of their IEMs. This may be far more important than the actual IEM they buy, which can sound like crap, when paired with the eartip that does not match very well in their ears,, for a specific IEM.