Pros: Price, clarity, voice emphasis, build quality
Cons: The cheap wire
I am still new to the audiophile world and the terminology still confuses me. I may or may not develop an "ear", but for me, these IEMs are spectacular when it comes to cost-benefit ratio.

You can read technical reviews elsewhere, as well as a detailed explanation of the sound signature. Being a relative new comer, I will cover more mundane characteristics: aesthetics, build quality, comfort, and where I found them the most useful.

I purchased the purple and blue version of the ZST. I'm drawn to bright, shiny things. Without the tips, the casual observer would be hard pressed to tell the are not custom IEMs. They particularly resemble UE CIEMs, though a tad less refined. The Cable is multicolored, though looks like muddled from a distance and feels rubbery.

Build quality
The finish is flawless, glossy and transparent. The beautifully laid out electronics are on display, which is a plus in my book. Each earpiece is stamped with a gold, stylized ZST. These earphones look like they should cost many times their asking price. The only part of the whole product that looks $20 is the cable which is finished to the same high standards but feels rubbery and the multicolor pattern looks muddy.

For me, ZSTs are very comfortable despite not fitting well within my or ear canal. This is a problem I have with all IEMs due to my small ear canals. The provided tips are somewhat fluted and provide a comfortable fit and hold. Unfortunately, the units stick out from my head somewhat, so I cannot use them in bed. Despite this, I never felt uncomfortable or sore after wearing them for several hours.

Overall sound impressions
The ZST monitors are excellent for listening to vocal heavy songs. Singers, such as Elton John, Billy Joel, and Lionel Richie, all of whose voices dominate their songs, benefited from the ZST sound signature.

Songs where the instruments are just are important as the singer suffer, but only because the instruments are pushed back in favor of the vocals. To use an example, while listening to Queen, Brian May's guitar work is de-emphasized and Freddie Mercury's voice becomes even more prominent.

Pink Floyd has many songs where the vocals are almost "just another" instrument. Comfortably Numb, with it's soaring guitar solos , strong string harmonies, and percussion back beats are lost to the vocals. They still sound good, but I do not get chills down my spine during David Gilmour's solos

Then I changed the cable and everything changed. Sometime back I purchased an after market braided OCC cable, which I believe to be the same one used by the Magaosi X3 but with 2 pin connectors which I used to replace the rubbery thing provided with the ZST. And the music soared. Comfortably Numb once again sent chills down my spine.

Buy the ZST for $20 and invest in a $40 OCC cable. Yes, you are spending twice as much in the cable than the ZiEM, but for $60 you will end up with a pair of IEMs which, to my ears, sound better than, for example, $180 Etymotic ER3XRs. Definite thumbs up at the current price, but when paired with after marjet cables, these babies can compete with IEMs costing many times more.
  • Like
Reactions: dabachata


100+ Head-Fier
Pros: Sound Quality
Shimmering highs
Cons: Mids
So after getting these in to see what a cheap double driver hybrid could really do, I was shocked.

The sound on these are really good, they're not gonna compete with any TOTL or my InEarz Euphoria's but for the price, I'm not sure there's anything out there with this kind of sound.

The lows can be felt, their natural sounding and deep. The high's sparkle and with almost no sibilance that I can detect. The mids were recessed a bit so for me in a live band situation they wouldn't do for vocals or guitars, but for live monitors for a drummer or bass player these are probably perfect. Definitely a V shaped sound signature.

The rubberized cable is not very good, but for $20 these are a great buy.

Raphael K

100+ Head-Fier
Pros: - Better sound than Xiaomi hybrid
- Much exuberant bass (it my case by case for listener)
- Crispy treble
Cons: - Bad cable clothing materials
- Little big housing.

It was my about 5th trial as I remembered to buying some IEM from KZ.
Judged to better than Xiaomi hybrid IEM, less bass but some exuberant - but still too much, ha - better for listening music in outdoor.
Around fitting on my ear was goor for me, but some people who wearing glass may not feels so comfort.
Just good to make an experience to take one more step to way of custom IEM from low cost under 20 USD.