The Ultra Cheap IEM Thread



Thanks. See above in reply to Antdroid!


I have recently been listening to the KZ ZS4 and have been enjoying it. Below is my review:

The ZS4 is the latest hybrid design from KZ amongst their recent batch of new releases. It is a dual-driver IEM featuring an 8mm dynamic driver for the bass and midrange, and a balanced armature for the upper frequencies. In this case the latter is the now familiar 30095 unit seen before in various KZ hybrid IEMs such as the ES3, ES4, ZST, ZSN, etc.

Presented in a simple white box with a picture of the earphones on the outer sleeve, a black plastic tray contains the earpieces, which have a medium-sized set of eartips pre-fitted. Below this you will find the detachable 2-pin cable and two further sets of silicone tips, which are the excellent KZ Starline type. The cable is a new design featuring a black braided wire and a stocky right-angled 3.5mm plug. The Y-split is the standard chunky one seen before in other KZ IEMs. There is no chin slider.

The earpieces are made from a clear, light, hard plastic in bright red colour. (They are also available in black). The left and right channel identification is displayed on the earpieces in a hand-written font along with the legend “hybrid technology”.

They are based on the ZS3 and have a complex knobbly shape which is designed to fit inside the ear cavity, and does so very comfortably. The fit using the pre-installed tips was very good. Inserting the earpieces and looping the memory wire round the ear, and then rotating the earpieces backwards about 30 degrees gave a perfect comfortable fit and seal. I found I could wear them for hours like this with no problem.

I employed my usual method of burning in before testing which involved running in for over 100 hours before listening critically. Initially I found the balance to be somewhat bass-heavy with a bright, sometimes sharp treble, but after the 100 hours burn-in the overall balance became mildly “V-shaped”, resulting in an exciting and entertaining sound. I have to say that these earphones were transformed by burning in more than any others I have tried.

The main source for auditioning was a Hifi Walker H2 DAP via line out with a Fiio L16-A2 cable and a Fiio A5 headphone amplifier. I found the ZS4s to be reasonably efficient and obtained a good output level both via the normal headphone socket on the H2 as well as via the line out. I tested the ZS4s with a wide range of music across various genres.


I already have the ZST, ES3 and ZS10 models which feature the 30095 armature driver for comparison. The immediate impression was of excellent clarity. The 30095 balanced armature displayed good texture and detail, having a very attractive delicacy in the upper register. Running a glide tone did reveal that there were some peaks in the treble but these were handled well, with only occasional harshness on high notes. There was a mild lift in the presence region which gave the sound an enjoyable immediacy. I would guess that the crossover point has been set at a lower frequency in this model compared to the ZST and ES3.

As the treble settled down it revealed a surprising level of detail. A good example of this was in “A story from the Rain” by Richard Burmer. This is a synthesiser sound-picture with lots of atmosphere. At the beginning, and near the end, there is the subtle sound of rain falling. This is at a very low level but the ZS4s reproduced this well, a very impressive performance given the price of these earphones.


The midrange was not too recessed, only appearing so in bass-heavy tracks. I found myself enjoying my music more that I had been doing for a while, having recently used more neutral-sounding IEMs. Vocals came over very well, Chris Izaak’s “Wicked Game” being a good example, with his voice clearly featured above the guitar and bass accompaniment. Lyrics were easy to discern, as evidenced in Richard Marx’s “Hazard” where the narrative was simple to follow.


Bass response was deep and powerful. It reached well into the sub-bass yet was not boomy or overwhelming. It was somewhat north of neutral and there was a small amount of bleed into the midrange. I was surprised how good classical music sounded. The warm mid-bass gave an attractive bloom to cellos and basses and emphasised recorded ambience, bringing the atmosphere of the recording venue into focus. “In Church” from the “Slovak Suite” by Novak sounded wonderful with the organ accompaniment displaying plenty of depth and power and the strings having a smooth, lush quality. There was plenty of impact, too, with the deep drum sounds in “Komarov’s Fire” by Richard Bone displaying excellent slam and power.


The ZS4s displayed a surprisingly good soundstage with good width and depth. The placement of instruments within the stereo image was also very good, which suited classical music well. In the “Suffolk Suite” by Doreen Carwithen, the sound of the strings, woodwind and brass was well balanced, all the sections of the orchestra emanating from the correct location.

Simpler tracks showed great intimacy. “I Wonder (Departure)” from Benny Andersson’s solo album “Piano” showed the ability of the ZS4s to reproduce the decay and harmonics necessary to hear the natural sound of the piano. The ambience and reverb in the recording was excellent. You could really imagine yourself in the room with Benny and his Fazioli instrument.

These are probably my favourite product from KZ so far. I have owned and tested seven models from their range and I definitely prefer these to the ZST, ES3 and even the ZS10. They improve on these with a superior treble response which is clearer and more expressive. They have a V-shaped, fun tuning without sounding unbalanced. With a comfortable fit, excellent seal and isolation and a very affordable price, they deserve an unreserved recommendation.

Chinese Brands - IEMs Discussion

Nice write-up. It is a great read.


Thanks Paul
I always like to include musical examples rather than too much technical information. Others can supply frequency charts etc. which are also informative, but I prefer to write from a music perspective. Glad you liked the review.


Great review! Have you listened to the ZSN or the AS06 yet? I like the ZSN the most of the KZ lineup. The AS06 just came in and it’s more laid back than what I’m used to in the KZ lineup which is a pleasant change. Posted some initial data on it in the Chinese IEM thread I started.


I have to say I do like the ZSN. The first KZ I’ve tried and first plastic shells (OK I cant lie… I was sold on that shiny faceplate :wink: ) but they’re a fun hard hitting bassy set with a nice clean trebble thats not too sharp.

And they’re super comfy, a great ‘fun’ sounding bargain set.

Plus they look awesome… I mean just look at them!


On the topic of cheap and Chinese, and because I mentioned it earlier, my V80 arrived a few weeks ago.

Great build quality and great screen and software… BUT for some reason it jusy seems really lacking in the bottom end with all my IEMs. The great 8ball eq can’t even fix that.

So if anyone is thinking of picking one up I’d avoid it if you like your bass… if you like neutral though then you’ll probably love it.

So I’ll probably be selling this on which is a shame as the actual device is brilliantly made!


You mean the AP80?

I really like the size and screen. It is missing something though, but it is considered a budget DAP. Im planning to write a review of it comparing against the new Xudoo X3-II as I received both at the same time (1 purchased, and 1 sent for review).


In an Ultra Cheap thread, I’d appreciate having some occasional reference to price. Under $5, Under $10, Under $20 or £ or ¥ or €


AP80 is roughly a $150 DAP.


OK, that helps for a DAP. My first Sony Discman was more than that, adjusted for inflation, but I even though I never bought a Walkman, the early cheap competition to the Walkman were probably inflation-adjusted about that range.

But what about the IEMs? a $20 IEM costs 4 times what a $5 IEM does. Does the price of either hurt?


The KZ ZSN @crezo just posted about is about $22-25 USD on amazon. Less if you buy on Ali-Express.


Ali-Express scares me a bit. I probably need a manual on how to buy on Ali-Express.


No, I haven’t heard the ZSN or AS10. I have the ZS10 but I find the treble a bit harsh. This disagrees with most opinions on this so I wonder if there’s a problem with the treble drivers.


You are not unique. The ZS10 is very bright.

The AS10 is a bit tamer.


It’s good to approach AliExpress with caution. Return shipping to China is challenging. I ended up returning an amp to a Chinese seller. Thing’s been "in transit " from Beijing to its final destination for more than a month now.


Thank you for that. I did try various tips on the ZS10, wide bores like Spiral Dots were too bright. Complys were too dull. Spinfits were better but there are some nasty peaks around the crossover between the Mid and treble BAs. The ZS4 doesn’t have this. Even the ZST and ES3 although quite bright are not as harsh.


Everything made by kz is bright and too much treble except this new AS06. The ZSN isn’t too bad but does have a peak in the upper mids which I can see some people bothered by with bad recordings or certain genres.


I have to agree with you. Especially the 1DD+1BA hybrids. A better choice I have is the Urban Fun Hi-Fi Beryllium hybrid which is much better balanced. It sounds very good with Spiral Dots.


After a few weeks testing and reviewing the ZS4 I have gone back to listening to the Yinyoo V2. Wow! Going back to a higher quality IEM really shows up the limitations of a less accomplished model. The detail, texture and soundstage are far better and the treble is so much smoother, open and extended. Have you tried these yet? They’re a real gem.