YINYOO Easy KZ ZST Colorful Hybrid Banlance Armature with Dynamic in-Ear Earphone 1BA+1DD HiFi Headset KZ in Ear Monitors Headphones Wired Earbuds IEM Earphones Gaming Earbuds (Colorful Without mic)

When I bought these in '18 I was merely looking for a pair of headphones that were inexpensive. I had no idea what IEMs were. My frame of references were: the OEMs that came with iPhones I had before and the Samsung AKGs that I traded up to later, and a handful of other budget headphones and wired earbuds from various companies. For $20 these outperformed anything I've owned up to that point. As if it took all the great bass, mid, and treble elements from every headphone/earbud I liked, removed all the elements I disliked, and put them into this thing. I couldn't believe it. How did these earbuds sound better and cost less than all the sound pieces I've bought before? Who the heck is KZ? I would later come to find out that this very IEM would become the starting line of the great budget IEM race.Fast forward 6 years. Tozo, Soundpeats, Anker, Moondrop, 7Hz, Dunu, etc. have saturated the IEM market with their offerings with a range of prices to compete with and even outperform tech giants. You know the ones. Some even have endorsements and collaborations from audiophile YouTubers. Even with all of these new products and the innovations made since this product came into the market, the KZ ZST still holds it's own as a go-to option. With 14K reviews and counting, The KZ ZST has become the template and baseline for all other IEMs to follow.That said, downsides:Cables: The fact it has cables is a con in this day and age. It wasn't an issue 5-6 years ago because smartphones still had headphone jacks. The cables went kaput after 2 years of everyday use. I thankfully bought upgraded IEM cables just in case and are what's attached to the ZSTs now. I haven't used the ZST after I got other IEMs and wireless earbuds in 2021 but I tested the ZST recently. It still works and sounds better.Build: The earbuds casings broke at the seams when I replaced the broken cables. They did snap back together and held together when retested them. For $20 it's not a big issue.Features: It plays sounds...and that's about it. No active noise cancelling. It's wired so tangles are a thing.Sound: I repeat this is subjective. Your own mileage will vary.Volume: Great. Plenty loud. It has drivers and that helps in out in that department.Bass: Great. It's not terribly aggressive and I prefer it that way.Mids: Clear vocals and instruments.Treble: Bright. Can get sibilant in some ranges.I maintain a score of 5 after six years of ownership. If you have a need for a wired $20 IEM that has stood the test of time, then these are still a good pick among MANY options.

I've never used IEMS before, and after getting these I'm never using ear-buds again. Why use cheap earbuds when I can have much better sound quality for the same price and form factor? I definitely know there's better IEMS out there, but these already sound really good to me, and I'm not really an audiophile so I don't really have a desire for the BEST quality sound. If you ever want to try IEMS, for gaming or music or whatever your heart desires, highly recommend these ones. They're cheap and if you don't like the fiddly cable, you can buy a different cable! I got a nice purple one that matches my setup. I guess the only downside is that they're slightly more fragile due to the tiny pins connecting the cables to the IEMS, but as long as you keep them at your desk or in a small cheap case you should be fine. Don't throw these randomly in a bag (I did that many times and they still work fine, but I've heard that you can maybe break them this way so don't be like me). You get what you pay for.. but honestly the sound quality of these are well beyond what I paid for.

The sound quality is great, comparing .flac files and MP3's side by side you can clearly hear the differences in bass and treble extension and response. So they're good enough for the average critical listener. Soundstaging is weak because of the in-ear design, but this in turn drastically improves bass response over a similarly priced pair of standard earbuds or headphones. Go ahead and put on your favorite live jazz albums (ideally in a lossless format) and just let these babies sing. Cymbals sound terrific, their shimmer is stellar.My only gripe is the fit. Everyone's ears are different, so adding the extra nub on top is a bit of a baffling choice. I can see how the nub may be very comfortable for some people. But for me, it pushes painfully along the ridge above my ear canal. I assume that I'll break into them eventually. But for now, they can be almost excruciating if worn for too long.For the price, they're absolutely worth a try to see if they're comfortable for you. Multi-driver tech like this has only improved over the years. These are the product of a long lineage of affordable iem's, and you can tell that a lot of thought was put into them. (besides that damnable indexing nub)