KZ AS24

How are you? How are they? In this current written review we talk about a brand that surely sounds familiar to you. KZ. Specifically, we will talk about the KZ As24, more precisely its purest version... the one that does not have switches. An iem full of balanced armor that is sold, according to the brand, as its flagship to date, being the most expensive kz iem so far. Even so, this product represents one of the best price qualities that I have been able to test in a product, offering certain sonic characteristics well above its price, especially at a spatial level.
KZ is entering a new era of maturity in developing and fine-tuning its products to appeal to audio's most discerning audience...those who regularly add new IEMs to their collections like you and me.
Why review the standard version?
I understand that for hobbyists, tuning switches will provide countless hours of fun. Flipping switches on and off is engaging, entertaining and satisfying.
But for others, like me this would be an irritating task that could be accomplished more quickly using a software-based equalizer. That's why I prefer to review the standard version and test, as always, with different amps, tips and songs.



The in ear is presented very fairly in the box. Kz does not usually offer as many accessories as other brands. We only have the pairs of small, medium and large size tips, the cable, the iem and a pair of memory tips which are the ones that come stock with the product.
So we have a simple little black box that is basically functional and efficient. There is no more or less. A small, simple and efficient unboxing.
Perhaps what is missing beyond more sets of tips or a more premium presentation is the typical carrying case, which is conspicuous by its absence. Considering the price of this product I think it is something that could have been taken into account.
Regarding the included cable, we have a 1.2 m high-purity silver-plated OFC. Quite attractive, lightweight. The 2-pin connection fits perfectly and is secure. However, and as you can see in the video when testing this iem I noticed very interesting sonic peculiarities so I decided to give it a cable with more of a premium feel. A cable that they had saved with 8 cores from the tripowin brand.



As for the design and construction, what can I say... it feels well made and the fit and finish are excellent. There is no discomfort despite its large size. I think the ergonomic shape helps compensate for the size. If it seems too big or if you don't like this, think about it...there are 12 balanced armors inside...12...and their weight is quite standard.
The look of the AS24 is attractive. At least I love it. It's like jewelry or precious stones. One of the nicest iems I've tried regardless of the price. The body of the AS24 is composed of several main parts: a lightweight, DLP-printed resin body, a high-precision integrated acoustic filtering nozzle, a diamond-cut bright stand, and a lightweight metal front cover.



This product has 12 balanced armature drivers inside. 2 for the mid frequencies, 8 only for the highest frequencies, 1 for the high frequencies and one for the bass...in other words, we have a configuration of 1 bass, 2 mids and 1 treble...the other 8 are used only filler for air which, as we will see, is a hallmark of the product.
The sound signature is mature and balanced. The sound of the AS24 offers lean detail with quite interesting clarity... a detail superior to any product under €100 in both hybrid and dynamic driver iems. Of course there are higher value iems which have less noticeable detail, such as, for example, the Ikko Oh5 although the latter offers more texture.
The transitions remain fluid and basically the resulting general coherence is really good, giving a very natural sound, but at the same time attractive...and not precisely because it has a shocking bass but because of its excellent dynamics with nuances. In addition, the soundstage is spacious and the images are precise for me its strongest point; making an ideal set for classical music sessions.

In terms of amplification, this product does not stand out for needing a huge amount of energy but we will always find a small improvement if it is amplified. In this case the improvement goes to the low and low midrange giving a slightly better impact. Its values are a sensitivity of 109 decibels for the customizable version and 112 for the one you see on the screen and just 20 ohms of impedance. Values that allow my laptop to extract practically 100% and with the Sonata HD Pro at half power (60mw at 32 ohms) it already sounds really good.
Therefore, it is an efficient iem that allows it to be used in a more portable way...a compelling reason why they would have included the carrying case.



SOUND SECTION – BASS
For a BA driver, bass reproduction is authoritative and rich, while remaining clean and well defined. The resolution and texture are good for natural instruments such as cello, double bass... I still consider the weight of the notes to be slightly thin if you are looking for warm, thick sound signatures with intense bass. It is not a bass comparable to other dynamic drivers but it delivers.
The bass delivery is satisfactory and appropriate for almost all genres except electronic or for sessions where you just want to enjoy and move your head.
Basically the bass extension is deep and without attenuation. I didn't hear any distortion when listening, to test, at moderate to high volumes.

SOUND SECTION – MIDS
The midrange section sounds natural to me, clear and full-bodied throughout the music. It doesn't feel like the body of the ikko oh5 but I do consider that it offers a very interesting body and doesn't feel thin at all. Let's say they are not too thin nor too thick. Its tonality is on par with the midranges of more expensive products because it exhibits an attractive, natural but well-layered sound.
You will be delighted with the AS24 if you mainly listen to vocal-focused music because female vocals in particular sound very attractive and present to me. Despite what the chart may suggest, the media never shy away from the back end. They are soft and do not give the impression of screaming.
So, like the technical-spatial part, the voices seem to me to be another great strong point of this product.

SOUND SECTION – TREBLE
I'm happy with the tuning and treble capability. Notice that they are not the cleanest and purest but they are sharp, revealing and detailed without causing great fatigue. I have not yet noticed a sibilance that bothers me but I have been able to find that strange sensation with some songs with a timbre that is somewhat characteristic of BA armature.
What is clear is that the treble provides a perfect balance to the rich and musical bass.
Basically the AS24 has a clean and clear sound. It has good extension up to the higher treble registers and the air or spacious sound feeling is evident as it has 8 key signatures for this purpose.

SOUND SECTION – TECHNIQUES
For me, the biggest strength of the KZ AS24 is the depth of the stage and the layers. He manages to display all the instruments very carefully, placing them with good distinction. The As24's soundstage may not be the widest or loudest, but in depth, it's one of the best so far I've tested regardless of price. On the x-axis of the soundstage I consider it to be not too far from the fiio fh9.
The new flagship therefore has a great sense of space and separates the instruments very well. Taking this into account, it might work better in terms of contrast between the instruments and the background.



The AS24s are really excellent. If you like genres more focused on classical music, soundtracks and even playing video games, they are an easy recommendation, especially as I said with such a favorable price-performance ratio that it is difficult for me not to recommend this product. For the price of the aforementioned fiio fh9 you can buy 4 Kz AS24…
Looking for a large, highly three-dimensional soundstage? I recommend you try it because it may satisfy you.
Are you looking for a natural and attractive sound? This is your iem.

Do you want the highest resolution for less than €150? This is your iem. I would say a greater range...to the point that it is not very far from the Quintet...but recently I was able to test an iem that is really interesting and that we will see soon, the mp145, which gives a neater sound.
I can only find those bassheads who are not very satisfied with this product because of its somewhat more reserved sound...or those with a smaller ear. This iem is really big although its fit is very good.
One thing must be made clear, it is a great iem but don't expect superior performance compared to iems well above its price. We have to be realist. It is very competitive, but up to the range of €300-€400 maximum. Still, it seems amazing to me.
The AS24 are mature, balanced and very flexible if you have the version with switches with which you will need time and patience to experiment with countless possibilities the subtle differences in sound.
If you liked it, give it a like, share the video and subscribe to support the channel and bring more and more products. See you in future written reviews and videos.

All the best.

The AS24 is a flagship all BA IEM from KZ

Product Information

Product model- KZ AS24
Frequency- 20-40000Hz
Sensitivity- Standard Version 112±3dB
Tuning Version 109±5dB
Impedance- Standard Version 20Ω
Tuning Version 20Ω~50Ω
Plug type- 3.5mm
Pin type- 0.75mm
Cable type- Silver-plated cable
Cable length- 120±5cm

1-Lightweight metal front cover
2-Sparkling diamond-cut bracket
3-2 Pin connector
4-Frequency division board
5-12 Customized BAs
6-3D-printed chamber
7-Metal acoustic filter
8-Memory foam ear tip

The box is typical and so is the cable unfortunately. While KZ has come a long way since that awful striped tangly mess of a cable that came with my ZST pro, I would have liked to see the Zar cable or JoyOdio cable come with the flagships. KZ for the most part have 4 basic tips, the White, The classic Starline, foam and those new spirally things. So, let's talk about the build quality, this is a solid design. There is excellent isolation and while they are big, they fit me comfortable. The look is a cool 3D design and I do like that.

Sound:
The Bass on the AS24 is neutral/ Balanced to boosted just a little, it has good speed in both Sub and Mid and excellent details. It works well with speed metal, Jazz and EDM.
The Midrange is balanced with good body and separation. Vocals are forward and clear as bass bleeds very little.
The Treble is open and airy with rich details and just enough sparkle and extension.
Soundstage: Is phenomenal, offering a wide-open sound with accurate placement and separation that can handle the busiest recordings.
Conclusion: The KZ AS24 is both technically proficient and enjoyable for a large variety of music, it's made well and sounds great.

DISLCAIMER

I would like to thank KZ for providing this unit. The AS24 can be gotten here: https://www.amazon.com/dp/B0C88VYDB7



SPECIFICATIONS

• Driver configuration: 12 balanced armature drivers - 4 x dual 31736 BAs, 2 x 29689 BAs, 1 x 30019 BA, 1 x 22955 BA
• Impedance: 20 - 50 Ohms (tunable version); 20 Ohms (non-tunable version)
• Frequency response: 20 Hz - 40 kHz
• Sensitivity: 109 (tunable version); 112 (non-tunable version)
• Cable: 2-pin 3.5 mm, 0.75 mm silver-plated OFC cable
• Tested at $124 USD (tunable version); $114 USD (non-tunable version)

Do note that there is a tunable and non-tunable variant available. The one that we are reviewing today is the tunable version.


ACCESSORIES

Other than the IEM, these are included:
- 3 pairs of KZ starline silicone eartips (S/M/L)
- 1 pair of foam tips
- Cable
- Tuning switch card pin



For something retailing at > $100 USD, the accessories are a mega disappointment; gear at this price range usually comes with a wider array of eartips, in addition to a case at least. There are even competitors that grace the packaging with modular cables or cleaning brushes once we hit the $100 mark. All these are absent in the AS24's packaging, and that is really not acceptable for the retail price.

The foam tips are suerpb for isolation and taming the treble, whereas the regular KZ starline silicone tips will boost the higher end and provide more clarity/soundstage.

Unfortunately, in addition to a lack of quantity of accessories, there is a sub-par quality too. The provided OFC silver-plated cable is thin and tangly, with microphonics. It does not even have a chin cinch! This is once again a far cry from the usual $100 fare, where we frequently see modular cables of much better haptic quality. During ordering, one can opt for a mic or non-mic version for this cable.

Lastly, we have the card pin to flick the switches, which we will talk about in detail in the following sections.

The rest of this review was done with the stock cable and stock starline silicone tips. No aftermarket accessories were used, so as not to add any confounders to the sound.


BUILD/COMFORT

The shells are made of dermatologically friendly resin, with some pseudo-diamond like faceplate. DLP 3D printed technology was utilized in the fashioning of the AS24's shells, to assist in providing strength and ironing out QC issues.



The earpieces themselves are pretty light. However, they are very large, which isn't unexpected considering the need to squeeze 12 balanced armature drivers inside. KZ advertises that they designed the housings after incorporating data of a myriad ear anatomies, but I found that the ergonomics was pretty hit or miss due to the huge shells. They protrude out of the ears quite a lot, and may be fatiguing for longer listening sessions.



Being an all -BA set, we won't talk about driver flex. Interestingly, the BA bass seems to be vented, which isn't common for an all-BA IEM. However, as a result of the venting, isolation is about above average, but not as solid as other unvented BA types.


DRIVABILITY

I tested the AS24 with the following sources:
- Apple dongle
- Cayin RU7
- Colorfly CDA M1 DAC/AMP dongle
- Creative Sound Blaster X5
- E1DA DAC/AMP dongle
- Hiby R3 Pro Saber 2022 DAP
- Khadas Tone Board -> Schiit Asgard 3 amp
- Khadas Tone Board -> Topping L30 amp
- Questyle M15 DAC/AMP dongle
- Sony Walkman NW A-55 DAP (Walkman One WM1Z Plus v2 Mod)
- Sony Walkman NW A-55 DAP (Walkman One Neutral Mod)
- Sony Walkman NW WM1A DAP (Walkman One WM1Z Plus v2 Mod)
- Smartphone

This IEM is relatively easily driven, but the impedance of the IEM does depend on what switch settings are flicked into play. Generally though, amplification is not required for the AS24.


INTERNALS/TUNING SWITCHES

This 12 BA behemoth houses the following drivers:
- 4 x dual 31736 array-design BAs handle the lower and upper treble frequencies
- 1 x 30019 BA is responsible for the upper midrange/lower treble
- 2 x customized 29689 BAs settle the midrange
- 1 x 22955 BA (vented) takes care of the bass.



On the bottom and back of each shell, we each have 1 tuning switch board (a main and an auxiliary one), with 4 tuning configurations for each board. The switches are extremely tiny, and those with poor eyesight or dexterity issues may have difficulty manipulating the switches. The switches seem to be of good QC and flick easily - I encountered other tuning switch IEMs that had stuck switches in the past, so thankfully the ones of the AS24 seem properly implemented.



These are what the switches do, according to KZ's marketing materials:




Potentially, we will have a mind-boggling 256 tuning permutations with the AS24!

From independent graphing of the most extreme of tuning switches, these are the potential graphs of what the KZ AS24 can sound like. This monster can sound like a bassy V-shaped set, to something more neutralish/U-shaped, to something neutral bright. The rest of the other 256 options fall somewhere in between these tunings. The versatility is really excellent, and is one of the feathers on the cap of this IEM. Indeed, I don't think there is an IEM out there that can boast of 256 tuning options haha.


Graphs of the KZ AS24 with the most extreme of tuning switches. 8 kHz is a coupler artefact peak.


SOUND & TECHNICALITIES

For the rest of this review, we will be utilizing the all switches up config, which confers a V-shaped tuning.

On this setting, the AS24 is a sub-bass focused set, with quantity just north of neutral. While not exactly sounding identical to DD bass, the AS24's vented design does allow the bass to sound more natural than other all-BA sets in terms of bass decay and movement of air. We have decent sub-bass extension and some rumble. Bass texturing is average - and may sound one-noted at times - though the speed is fast, with minimal mid-bass bleed.

The lower midrange is recessed on this configuration, but without big bass to encroach here, it is quite transparent and clear, allowing instruments to be easily pinpointed. The upper mids are forwards without overt shoutiness, unless used at very loud volumes (Fletcher Munson curve).

With this setup, the treble is quite bright, with moderate air and sparkle. There is marked sibilance and some harshness noted in the lower treble region, with overemphasized high hats and cymbals. Treble-sensitive folk might want to experiment with foam tips, or perhaps check out the least bright switch settings.

The AS24 sounds very metallic in terms of timbral accuracy, and this is arguably one of the major weaknesses of this IEM. Vocals sound nasal, and acoustic instruments like strings, woodwinds and brasses sound artificial. This IEM may not be the best option for timbre freaks or for genres like jazz, vocals or classical as such.

Where the KZ AS24 aces (and redeems itself), is in the technicalities department. Resolution, clarity and micro-detailing are very good for a low $100ish set, with solid instrument separation and imaging. Soundstage is about average in width, but has good depth and height.


COMPARISONS

Some $100ish USD tunable gear will be taken out for comparisons against the AS24.




Hidizs MS3

The MS3 has 3 tuning options via nozzles, from a warmish bassy tone to a neutral bright signature. On the gold (balanced) nozzle, which is the mid-point tuning of the 3 options, the MS3 is brighter than the AS24, with greater air and sparkle, though it is probably more fatiguing than the AS24.

The MS3 has similar instrument separation, but has better micro-detailing, soundstage width and imaging. The AS24 is better in soundstage depth.


Kiwi Ears Quartet

The Kiwi Ears Quartet has 4 tuning options via switches. Across all tuning switches, the Quartet is darker in the treble, with a thicker note weight and a more natural timbre.

Unfortunately, the Quartet is leagues behind the AS24 in technical chops, with inferior soundstage, micro-detailing, imaging and instrument separation.


TRI Starsea

The Starsea has 4 tuning options via switches, but they are all quite similar tonally. So from a versatility point of view, the AS24 is superior.

The Starsea has slightly better imaging, but otherwise loses to the AS24 in other technical areas such as soundstage, instrument separation and micro-detailing.

The Starsea has a bad pressure suction effect on the ears, plus driver flex, which may be deal breakers for some users.


CONCLUSIONS



KZ and TRN are famous (or perhaps infamous?) for their multi-driver nuclear race, and KZ has upped the ante with 8 tuning switches to provide a possible 256 tuning permutations in the AS24!!! KZ is quite extravagant to say the least! Unlike other "tunable" rivals which have minimal or very subtle changes in sonics, the AS24 does have quite marked tonal differences on graphing.

The AS24 also sports good build and easy drivability, and technicalities-wise, it is one of the better sets at the low $100ish range. Despite packing BA drivers for the bass, the bass does not sound as anemic as some BA bass IEMs due to the addition of venting.

Well, considering that one can get multiple pokemon - 256 to be exact - to evolve out of this primary KZ pokemon, the versatility is really overwhelming (and may be an overkill). On the flip side (no pun intended), some lay consumers may be confused as to what the tuning switches do, especially if they do not have graphing rigs.

There are some other areas where the AS24 loses marks in my book. Firstly, the accessories are horrible, and I've seen sets at 1/3 the price which pack way more goodies. Comfort is also hit or miss due to the large shells needing to accommodate 12 drivers per side, and the tuning switches are really miniscule - folks with eyesight or dexterity issues might find it problematic to toggle the switches. One major bugbear of mine is the artificial timbre, and this IEM may be a bit peakish for our treble sensitive brethren on some settings.

Nevertheless, the above average isolation, versatility and technical prowess does make this IEM a suitable option for audio work or stage use, and analytical heads and folks wanting something for critical listening will not be disappointed here. Listeners who prefer something more natural or organic sounding might want to look elsewhere though.