QKZ CK9 Earphones Review – Bass Gone Wrong

First Impressions

Out of the box, the QKZ CK9 looks like your standard QKZ pair. 

In terms of how they look, nothing really stands out and if you’ve had a couple of QKZ earphones before, then you’re already familiar with their design. 

Since I’ve reviewed the CK8 and CK5, I’ve had nothing but high expectations for the CK9. I wanted it to be equally as good as the others since I’ve had the impression that the CK line was a hidden gem that performs quite consistently. 

Upon first listening to it, I was met with this thick veil that blanketed the midrange. At first, I thought it was just a common case of smearing but the worst has yet to come. 

After further listening, I realized that the treble was also subdued. I’m at a loss for what to say about the upper end being dominated by the bass. 

Most of the technicalities are going to be derived from the treble so the low-end interference shoots the CK9 directly in its face as it obliterates any kind of saving grace. 

Build Quality

The QKZ CK9 has an all-plastic shell with a non-detachable cable, being on the cheap side and all. 

Overall, I do like its shape and the fact that it’s black but I’m not a fan of its design though – the faceplate has a big letter F in white, and just below it is small white text that reads: double moving coil. 

I can understand if they want people to know the engineering side of things inside the unit but they’ve already done that through the advertising. 

The design is just tasteless and could’ve been a simpler sleek black faceplate albeit a bit plain-looking. 

Fit and Comfort

With its average ergonomic shape, the QKZ CK9 is generally comfortable. 

The pre-installed tips were too small, resulting in a horrible fit that affected isolation. There was a small gap between the shell and my ears that let a little bit of sound in. 

Replacing the tips with the bigger-sized tips included in the set was a good decision as it fixed the fit issue. 

I don’t think it’s the best shape as I prefer those round resin ones you’d see on Kiwi Ears IEMs but they’re not bad.

Sound Quality

The QKZ CK9’s alleged tuning was supposed to be a V-shaped signature but in this case, it sounds more like an L-shape signature, with that huge bass cascading down the whole frequency band. 

On songs where the bass is light but still present like Yuseiboushi by Eve, you get a sense of the CK9’s real tuning as the other frequencies are more audible. 

Despite the lack of emphasis on the song, the midrange still had that persistent murkiness latched onto it. Upping the volume remedied this to an extent but it introduced some sibilance, forcing me to lower the volume again. 

The upper midrange seemed to have a good level of clarity – take note that this is from the specific song from Eve. 

A lot of songs I’ve listened to with the CK9 sounded really bloated, muddy, and hardly discernible with their lyrics. Coherency and consistency are a problem aside from the glaring issues with the subdued mids and treble. 

The part I hate with a badly tuned IEM is that a buyer would try to find some kind of loophole to make do with the tuning, and it’s probably extreme song sorting or just getting used to lousy sound quality. 

It’s cumbersome enough to make a playlist that you like, and even more so with making a playlist just for an earphone to not suck. 

At the end of the day, there are a lot of disjointed things about the tuning because of how the bass is tuned. 

For a V-shaped signature, its problems sound needlessly complicated and far from the minor gripes I’d normally have from a relatively competent earphone. That within itself is the flaw because it’s the most basic signature. 

Bass

Despite the massive bass presence in the QKZ CK9, the sub-bass isn’t at all very defined. What it outputs as quantity loses out on its quality. 

The sound can reach a good depth but lacks a bit of texture. This makes the low end pretty erratic and all over the place. 

The mid-bass has a moderate impact but is slow in its dynamics. The bass is pretty balanced when it comes to songs with a more relaxed low end. 

The rumble is tamed by a lot and the mid-bass delivers good thump and rhythm. Of course, this occurrence is seldom as a lot of modern songs always have bass. 

All in all, this frequency band is the problem region. I would’ve liked for some roll-off on the sub-bass and a little more note texture to make it more satisfying than obnoxious but, alas, it’s the wishes of a dreaming man.

Midrange

The midrange of the QKZ CK9 sounded pretty horrifying the first few times of listening. If I was listening to pop, it almost always ended up being a nightmare. 

The lower midrange sounds recessed and the degree would depend on how much bass the song was calling for but for the most part, it’s subdued. It sounds muffled and fluffy, like listening to a song through multiple layers of blankets. 

The note definition and placement in the soundscape are significantly affected, making the low mids sound laid-back and often overwhelmed. 

The upper midrange has a decent amount of energy and clarity to it. It’s the only thing in the frequency that’s stopping the bass from fully submerging the mids into gunk. 

All in all, the lower mids are just unpleasant, while the upper midrange’s performance is gallant and admirable.

Treble

The treble of the QKZ CK9 has got to be the one that suffers the most. 

While the mids happen not to go overboard the ship and drown in the eternal abyss that’s the bass, the treble does. 

The details sound awfully fluffed out and muted, and the transients are distorted and sound unnatural. The sense of air and extension is also compromised. 

As the treble contains most of the sonics that makes up the technicalities, the bass ruins everything up top, throwing all of the possible potentials the CK9 had as a silver lining.

Technicalities

The staging, imaging, and transient response were all sub-par, if not worse than average. The treble took quite a large hit from the bass, so I’m not surprised that the technicalities suffered. 

Conclusion

If there’s something that you can learn from all of this, aside from the obvious fact that the QKZ CK9 is bad, it’s that less is more. 

The biggest mistake that the tuning engineers probably made with the CK9 was trying to overdo the bass to add fun to the signature. 

But ultimately, it ruined the overall balance and disrupted the other frequencies. 

If you’ll be using these earphones for J-pop or K-pop, then you’ll be somewhat fine. While that much is satisfactory, I think there are other QKZ earphones that can do so much more with the CK9’s price.

I sincerely wanted to like this set but I’m quite disheartened to say that I can’t recommend it at all.

This post was last updated on 2025-01-16 / Some images from Amazon Product API & some links may be affiliate links which may earn us a commission from purchases.