S12 Pro

**TL;DR:** While it performs admirably for its price, it doesn't break the "budget ceiling". **Just a heads up:** *I’m just an enthusiast, not a pro. My opinions are 100% my own and unbiased by any sponsorships. Take my words with a grain of salt! Please treat this review as one person's opinion rather than a definitive technical analysis.* **My setup/testing gear:** * **DAP:** Oilsky G88, TRN Black Pearl * **Eartip:** HE Sonic Galaxy Edition * **IEMs:** **GK Streak**, **Letshuoer S15**(200-300$), Tangzu Wan'er 2(20$) **Pros:** * Great tuning * Good sound detail and clarity * Fits great in my ears **Cons:** * Sound stage is not good for me * vocals feel slightly recessed I think **Sound Review:** **Bass:** Very good. The bass has a strong impact, but it remains remarkably clean without any muddiness. However, I'm more vocal&mid guy so sometimes I feel a bit too much bass. **Mid&Vocal:** Sometimes I feel the vocal is "recessed". **Treble:** The treble can be a bit sharp at times, but it’s not a deal-breaker for me. **Soundstage:** Soundstage is definitely the weak point of this IEM. It feels quite cramped compared to my Letshuoer S15, and even seems narrower than the Wan'er 2 (though I haven't done a side-by-side comparison with the latter to be 100% sure). **Overall:** I can't deny that this iems is great for its price. I didn't expect this sound quality from 20$ class. However, I won't say this iem is like giant killer, like "You won't need 200$ iem lol haha" kinda thingy. It is clear that the Streak falls short of true mid-range iems when it comes to soundstage, etc. While the S15 has great sound stage and a calm, warm-neutral tuning, the Streak is much more energetic and fast-paced. Maybe some people will prefer more the Streak, but I like my S15's calm-chill sound. Any questions are welcome! Sorry if my writing sucks cuz I'm Japanese.

Try a liquid silicone eartips like Nice HCk co4 or the Angelears AE1000, spinfit w1 Alternative iem with small shell is s12 ultra

So I can see eveyrone is meming without actually giving advice. It's your first IEM and I get it, sounds great. I was impressed when I got my KZ SN10 years ago. I didn't really get an idea of their failures till I tried some other headphones. My main use case is riding on the motorbike. I had my KZ at 95db and didn't really notice a problem till I was listening indoors in a quiet room. They were painfully loud. After this I got some better isolating ones, reduced the volume to safe levels and heard so much more detail in the music. This was my Letshoer S12 Pro's. They were fine on the motorbike until I went on the motorway and the isolation can't keep up. My newest pair is a Kiwi Ears Orchestra. They isolate me from outside noise by an unbelievable amount, and have incredible detail as well. If you are happy with what you have, enjoy. If they lack in some areas, you can read reviews and move to a better pair. The market is ever shifting with expensive tech ending up in the cheapest headphones. You really can get exceptional sound out of very cheap chifi headphones. The hardest part is picking one to buy.

Haha. God I hope not. I am getting married soon, and this is my "last fun purchase" before I get more responsibilities. Thank you. :D I meant that I will sell more of my cheaper pairs such as s12 pro, dunu kima 2 and such. I do not think that I can sell all of mid mid-tier sets. Even if I do, I definitely can not sell DaVinci (fun set for me) and Dusk (First IEM). Interesting, I guess I will need to listen to my cheaper pairs again. If I may, what IEMs do you have? and what genre do you listen on them?

My first ever KZ or GK product, I've been purposely avoiding them because of potential QC Issues. Finally decided to pull the trigger on my first KZ IEM, a KZ PRX so I could compare side by side to my Artti T10 and Letshouer S12 Pro which I'm very familiar with. I was surprised how minuscule and basic the KZ packing was but that was expected for such low price. Immediately switched stock cable and ear tips as well. I put TRN Sea Serpent with a 4.4mm plug and Tri-Clarion TRN ear tips (L). At the beginning, I had like a little distortion like a constant popping/crackling sound on the right shell, a couple of minutes after it was gone. I'm pairing my KZ PRX with 1-bit discrete DAC (Cayin RU7) and K13 R2R DAC's, working at 43% of internal volume for RU7 and 35% for K13 R2R. Audio quality compared to my Artti T10, I could safely say it brings 90% of the Artti T10 in terms of sound clarity and detail and about 80% of my S12 Pro. I tested it with my complex latin tracks which use multiple percussion instruments, brass, piano, bass and male-female voices simultaneously. Not bad for $20 bucks. Next, I will be probably trying other KZ products like CCA Hydro and KZ Symphony to see how they compare with similar priced products like Dunu Kima 2, Simgot EA500LM and FiiO FH3. Just in case I bought KZ PRX on my dime so I'm not conditioned to say anything positive about it. **Update on 2026-04-04**. After my initial test, constant popping sounds came back on next day and it's annoying and unbearable specially under ballads, soft rock, acoustic or unplugged albums. Tried 4 different cables, both 3.5mm and 4.4mm, tried 7 different ear tips, and even audio sources, both my Mini PC's, a MBP, a Samsung S25Ultra, S25FE, A52 5G, tried also with 7 different Portable DAC's, issue remains. I contacted KZ seller(a highly reputable seller) and he responded me the first time, and has been ghosting me for the last 4 days after I replied. I requested a replacement for the right shell on my dime (shipping expenses only) or to buy a KZ ZS12 PRO X IEM, so he can combine shipment. I don't want to escalate to AE again. So far, out of 25 purchases in the last 2 months, only 2 had issues, the other one was a DOA cable for a TRN IEM. If worse comes to worse, I'd still buy another KZ PRX from Amazon this time, since I really like KZ PRX sound signature with a balanced connection and R2R DAC's. I guess, KZ potential QC issues are not a joke, or maybe I should start playing the lottery. **Update on 2026-04-05:** After 4 days with no response from Seller, I decided to escalate to AE after I carefully explained it on detail to AE customer service(bot), they approved a RMA with prepaid shipping label right away, I guess it matters when you spend regularly on AE and have zero(0) returns on your file, now my surprisingly good KZ PRX is going back to China. I was going to order last night, another KZ PRX, KZ ZS12 PRO X and KZ AM16 balanced sets from another seller, but decided to hold on future KZ purchases, what are the odds I got another KZ IEM with QA issues?, possible higher than ordering TRN IEM's. I took the plunge and ordered a full line up of low cost Planar IEM's instead: Hidizs MP143 Salt, Sgor Luna and TRN Rosefinch. https://preview.redd.it/ctr75ptu8mrg1.jpg?width=2286&format=pjpg&auto=webp&s=a789f41beded2123cb7bd7fd54cb81a864e96f17