KZ-ZES Review – what makes this IEM really sing?

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I’ve spent time with the KZ-ZES in the office and at home over long listening periods.

My source was either my Macbook Air M1 or my iPhone 12. I have a FiiO A3 which can play as a little booster for these if you have a headphone amp or amp/DAC. They are powered pretty well as they are though.

This is impressive considering electrostatic drivers tend to like a little more power, even low wattage units.

I changed things up a little for this review and mixed my reference tracks. While I normally bounce around this list of tracks to test your HiFi, this time I went where the KZ-ZES were leading me.

I tend to do this more and more in my reviews as it gives me both sides of the coin – how they perform with set genres and styles and how they perform with music I think would suit them even better.

I nearly gave these a 3 Star and walked away

When I first tried these in the office I was in a passive-aggressive mood. This usually requires some form of heavy listening. Too Close to Touch, Our Last Night, 30 Seconds to Mars, Underoath, Oh Sleeper, Ice Nine Kills.

This didn’t go well. Immediately I thought “another budget IEM with inflated bass and no upper clarity or midrange dynamics.”

To end there would never be acceptable. As someone who takes their reviewing responsibilities very seriously, I knew I needed to shelve them until such time as I could try more genres when my mood improved.

I always see what other people are saying about IEMs after I review them so it doesn’t cloud my review. This time I made an exception and wanted to give KZ the benefit of the doubt. Many other people thought these sounded great so back to the audition phase I went.

Things on the second round improved greatly with the KZ-ZES

If we glance back a few lines you’ll see that I decided to try tracks that would sound better specifically for this unit.

One the second round I tried a little more ambient approach. London Grammar, Vancouver Sleep Clinic, Damien Rice.

Now I started to appreciate the balance of the 12mm driver and the low power electrostatic driver.

So I continued to audition through additional tracks to see what else might bubble up to make the KZ ZES shine a little more

Fit is key, as I always say

Like any IEM the fit is the most important part of the journey. Play with the silicon ear tips you get even if you think the mediums that come pre-fitted feel good.

Unlike most KZ units, I found these a touch looser in my ears but a small tweak to the placement and the bass and full sound returns.

My complaint for these is the same as any other IEM cable. That is, they lack a tensioner on the cable. This makes it possible to tighten the two ear cables at the back of your ears. Without the tensioner, it makes it hard to really use these as live music IEMs and even on your commute.

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Sound Quality

Overall, these things sound great when you send the right things to them.

Rock music sounds good but not great. The Bass is great but the mids and trebles for me start to sound like a ‘pizza’. Just all thrown in there and all the instrumentation and vocals smashing into your ears while being squashed into the same frequencies.

That sounds quite negative but they’re not bad, just not great for rock/metal music.

Now, before you click back and search for something better, bear with me.

The next genres were so much nicer. The ambient music I mentioned above certainly fits in well.

I believe these suit anything where there is a deep bassline and where the mids and treble range aren’t too crowded. Hence why London Grammar, The XX, and a lot of dance or deep house work nicely with the KZ-ZES.

Pop music also came across well.

I tried some Rap and Dance. The bottom end was great but you might find yourself wanting the rap vocals to be a little more prominent. Certainly still enjoyable in part as the bass helps carry it.

I should note the Bass is full and natural but not subwoofer level deep.

Aquilo also sounded great and if you listen to Sofia Karlberg’s ‘All the Stars’ cover it’s quite delicate although it also shows how the vocals could have a wider frequency response for an even fuller and enjoyable vocal track.

Sohn, another suitable genre style for the KZ ZES to perform well.

Bass

The bass is great. Full, deep, and rich. The sub-bass isn’t amazing but that’s OK at this price. It’s warm and feels well-rounded without sounding like it’s coming through a wall of cardboard which is a regular complaint of mine with budget IEMs.

Sub-bass response at this price is tasty which I put down to the larger than normal 12mm dynamic driver which can reach wider.

Mids

Mids are nice but can be a bit thin on vocals. You get hints of the vocalist leaning over the microphone which is really nice but you sometimes want a little more depth in the mids.

‘Reconsider’, the Jamie XX Remix sounds great even though you might want a little wider frequency response in the mids. The overall track is quite sublime to be honest. The sound stage is excellent and the separation clean and enjoyable.

Missing – Round Remix / The XX – Hivern Remix also meets with my personal approval. Really nice stuff.

Pop Music does well with the KZ ZES. Dua Lipa’s ‘New Rules’ sounds great. Nice PRAT on this track with the bass standing up well, the mids helping the little pop notes shine and the treble carries the highs sufficiently to make my feet tap.

For tracks where you have a select few instruments working in the mid frequencies, these do a good job of bringing the tracks to life.

Treble

The treble is helped by the electrostatic driver which increases the top-end response to well beyond your hearing abilities.

I like treble, so I tend to like electrostatics. The treble on the ZES is nice without being over the top. It’s not harsh and doesn’t leave you feeling fatigued and tired. If the mids were fuller the treble would only shine brighter.

You’ll hear NZ/Eminen spitting on the microphone and Aurora breathing over her microphone.

In fact, if you want to try some ASMR have at it.

Summary

The KZ-ZES are a great budget IEM if you love to feel deep, warm bass without the bloat.

They suit clean, uncluttered audio tracks that allow the ZES to present each without too much conflict and mess.

If you like smooth tracks, ambient sounds, deep house chill, pop, dream pop, indie electronic, and similar then you’ll be rewarded with a really nice and affordable unit.

The bass alone is enough to recommend these in my opinion. Maybe not for rock lovers, but most else will do well.

Fatigue is low and comfort is good.

Not perfect in the full sense, but really good at some things, and that’s OK.

Questions, comments, quibbles? Fire away in the comments below.

This post was last updated on 2024-12-03 / Some images from Amazon Product API & some links may be affiliate links which may earn us a commission from purchases.