Disclaimer: The KZ AS16 were sent to us free of charge in exchange for our honest review. We thank team Linsoul for that!
My video review can be found right here:
Last week we reviewed the impressive FH7 IEMs from FiiO, this week however KZ AS16 from Knowledge Zenith entered the spotlight and we putting them under our magnifying ears.
Knowledge Zenith or KZ for short it’s a first around here and I am told this is their latest, the greatest and their most expensive IEM to date.
AS16 are not your average IEMs because they are using multiple balanced armature (BA from now on) drivers in detriment of all-dynamic or hybrid designs. AS16 are called this way because they have a total number of 16 BA drivers to make the music sing, or 8 drivers per side.
KZ used their R&D team for about 15 months to came out with their different AS16 IEM.
I was surprised a bit to get such a small package, this is the smallest black box I ever received, it comes in a nice but plain looking card-board packaging.
Inside you’ll be greeted with a nice message from the KZ team that reads: “Don’t forget. The original intension is use headphones to enjoy music”. There is also a wide metal plate that informs you that AS16 is using 16 BA drivers. The IEMs themselves are sitting in a nice protective black foam to absorb accidental drops or shocks.
Underneath it you’ll find another 2 sets of silicone ear-tips, since the medium sized one is already pre-applied on the AS16, you have a total of 3 sets of silicone ear-tips. There is also a very nice-looking braided cable, seems quite durable and very flexible. The conductors are pretty thick and should resist a lot of use and abuse. My particular pair has a small one-button remote on the right side of the cable that houses a small mic inside. Pressing it once will pause your music, twice will play the next song and pressing thrice will get to the previous song, it also can be used with a smartphone to answer, hang-up or reject your call.
There is also a small warranty card and a user manual, in both English and Chinese – and that is basically it. Would like to have a small carry case for this price, but maybe their next iteration will have one.
Looks & Build Quality
AS16 looks pretty nice and very well put together. The shell is made from pleasant resin (Acrylic) using very reliable 3D printing techniques. The outer part is actually a zinc alloy cover that looks impressive and feels great to the touch.
As you might imagine housing an impressive number of drivers per side would lead to a larger than usual shell. However, since it has a smooth and natural shape and a longer metallic nozzle the IEMs are sitting very comfortable once put inside.
The BA drivers are sitting tightly, without any wobble, same can be said about the cross-over and the internal wiring. Everything was squeezed inside tightly and firmly for a nice look and comfortable wear.
Tech inside AS16
AS16 is using 8 BA per side, 2 bigger ones will play all-bout that base, 2 mid-sized ones will put soul into the midrange and 4 smaller drivers will take care of the treble.
KZ is proudly informing us that at 1kHz the treble is boosted by about 7-8 dB, I’m not really sure how I feel about that.
There is also a custom made cross-over to split all those low, mid and high-frequencies away and a 3-way nozzle to put them back into your ear. For this particular model KZ developed a new three-channel acoustic duct structure for a higher transparency level and for a balanced FR.
AS16 is of course using a detachable cable, made out of high-quality OFC conductors, the IEMs are connecting to the cable using a 2-Pin connector that looks very familiar to the one found on the Ultimate Ears IEMs, it might be even the same connector.
The 2-Pin connector is not flushed inside the IEM but it is on the outside so please take extra care when inserting the cable or pulling it away to not bend the pins. The space inside the shell is already super tight and makes sense putting those pins outside.
AS16 have a nominal impedance of 15 Ohms and a sensitivity of 105 dB so it’s pretty easy to drive. Even with weak headphone amplification as smartphones or laptops they worked nicely. AS16 are also covering a super wide 20 Hz – 40 kHz frequency area. I consider AS16 to be quite sensitive to hiss and background noise so I recommend a hiss-free with a blackest background as possible audio source.
For the record using most of my desktop headphone amps revealed a faint hiss, especially with xDuoo TA-10, much less with Burson Playmate and almost inaudible with Headamp Gilmore Lite Mk2. Latest portable offerings from FiiO worked much better, the M6, M9 and M11 worked just wonderfully with them and would make a nice pairing.
I couldn’t test them balanced since 2-pin connector cables are not very wide-spread nowadays and don’t own such a cable terminated in a 2.5mm or 4.4mm headphone out, so I mostly used KZ AS16 with my portable DAPs.
AS16 have a super clean, vibrant and energetic bass. It is also very detailed with few layers here and there. However, there isn’t a lot of weight and slam to it.
With stock ear-tips AS16 are especially weak in the sub-bass area and it couldn’t be awakened even with desktop power.
Actually, there is little to no information up to about 40 Hz, my favorite electronica tracks had less weight, slam and sounded thinner than my reference IEMs. If AS16 are losing ground in terms of slam, weight and sub-bass performance, they win ground at everything else as the bass notes are always super clean, layered, fast and impactful and not a single time were muddy or dirty.
An idea never left me alone and that is using the AS16 with other ear-tips, I wanted to test them particularly with the memory foam tips and with Spin-Fit tips, with them some of my complaints faded away. Sub-bass improved, slam improved, most importantly the ear-seal improved so it is just natural for bass to gain presence and quantity. If you care about bass please buy separately memory foam tips.
Mid-bass tones are fairly neutral but again sometimes are lacking in weight and slam. I really recommend using the memory or Spin-Fit tips to awaken them. If you feel your AS16 are lacking a lot of bass weight you might have a fit issue, like I had. A bad seal always gets you a weak bass response.
AS16 are not having crazy amounts of bass slam and are not dwelling super deep into it, for bass lovers there are better solutions, however much more expensive as well.
Moving fast forward to midrange, things are greatly improving but mind you it is still not the best part of AS16. Transitioning from mid-bass to lower midrange there is a small drop and few voices are having a lesser weight to them. Lower midrange is mostly lean and can be dry sometimes. Vocal performance is not very imposing or soul reaching.
In defense to this area, mid tones are sounding crisp, clean, have a good outline and a bit of sharpness. Vocals are staying on top of bass and treble and are very centered, so midrange performance is fairly good.
Upper-midrange is so much better. There is a lot of spark, zing and lots of presence. As Knowledge Zenith told themselves at 1Khz there is indeed a rise of about 7 to 8 dB so everything is much more defined, outlined, super sharp and clear.
For me this results in an un-even frequency response. Truth to be told I never heard such a voicing in a pair of IEMs, a truly unique experience. String based instruments have such presence and a lot of spotlight that in the long term can became tiresome.
Ladies and Gentleman, I think where AS16 really shines is in the treble area. I never tried such a treble extended performance. It can be overwhelming at first, especially if like a warmer, calmer and rounder presentation AS16 will shock you at first listen. There is a lot of treble nuance, shimmer, few hidden details that you never knew were there. KS AS16 is really opening that treble presence to new levels.
However, if you are sensitive to hot treble AS16 will not please you as they are the exact opposite of smooth and relaxing.
IV. Transient Response & Detail Retrieval
AS16 has an impressing PRaT (Pace, Rhythm and Timing) and awesome speed and impact. Combine that with a detailed, magnifying glass like presentation and you get a general idea what to expect from them. AS16 will dissect to pieces every track, good recorded music will sound great and music with bad mastering and a lot of noise is almost unbearable to listen. AS16 is not offering a smooth and refined listening experience, but mostly a monitoring like experience. If I would assign a desktop headphone sister to them that would be certainly the Sennheiser HD800 as both share so much together, minus that open wide soundstage HD800 is having.
V. Soundstage & Depth & Imaging
Due to high transparency levels and great detail retrieval, AS16 is having a quite nice pin point imaging and holography. Sounds are clearly spread out around the listened and I can easily appreciate the distance between them and myself. Depth is great actually and at this price level is almost unbeatable
Soundstage size is normal, mostly at the shoulder level, so not super wide but not narrow at all in the same time. AS16 are not forward sounding and will put you few feet away from the music band most of the time.
Since AS16 is all-BA design the decay of the notes is faster than usual so everything will happen fast & furious. Every note will not linger too much and will die fast with little to no sustain. Remember lack of bass slam and vibration? That is because AS16 have no real sustain and a very quick decay.
VI. Background noise & Source Requirements
AS16 are very source dependent and would sound different with desktop or portable sources. With FiiO M11 DAP, KZ AS16 are dead silent with a noiseless background. With all my desktop sources it has a bit of hiss, but that is the issue of said source and not of AS16 themselves.
AS16 are very easy to drive and this is why I strongly recommend using them only with hiss-free and clean as possible portable solutions.
I would also use them with a warmer source where bass and lower-midrange is emphasized for a more linear experience, for a fuller and a more natural sound signature.
FiiO FA1 (~100 USD) vs KZ AS16 (~130 USD)
FA1 are much smaller and lighter so are a bit more comfortable to wear. In terms of build quality KZ AS16 are much better, with a zinc alloy metal cover and a thick smooth resin outer shell, they just cream high quality. In terms of packaging FA1 are slightly ahead since they have a small carry pouch and 6 pairs of ear-tips instead of 3.
In terms of sound quality both units are so very different.
FA1 are sounding slower, leaner, with weaker transients. FA1 are also more forward sounding with a lot of midrange presence. There is so much of it that it mutes a lot of bass and treble performance. FA1 is very rounded sounding with weak sub-bass and upper-treble. FA1 are also not very resolving and would not extract a lot of information from your favorite tunes.
AS16 are detail retrieval monsters with a very accurate pin point imaging, have better transparency and a much better treble – it is very extended into the subsonic levels.
AS16 however suffer in the lower-bass and midrange where there isn’t a lot of presence there. AS16 are mostly analytic and very neutral and FA1 are euphoric and warm, two very different presentations.
All in all, I think AS16 have more impressive traits and technicalities.
Knowledge Zenith is encouraging us to compare AS16 with IEMs up to 10.000 yuan (~1450 USD) a thing that I will not do since I consider pricier IEMs more linear, more extended, with better packaging and accessories.
Now into the conclusion I can certainly say that KZ AS16 have a quite unique sound signature that will impress a lot of people and shoo away bass addicts.
Packaging wise you’ll have everything inside, but I recommend hunting those memory foam ear-tips for a much better seal and bass performance.
At the end of the day AS16 were made for critical listeners that care about their recording quality, about their upper-midrange and treble the most. If detail retrieval, transparency and pin-point imaging is what are you looking for in an IEM, I think AS16 is very much for you then.
Considering everything they did right for a ~130 USD IEM the rest can be just overlooked as KZ AS16 sounded impressive at this price point.
- Great fit and finish, very good comfort as well
- Good depth and soundstage with an airy presentation
- Fast transient response
- Detail retrieval monsters with great transparency
- Lean and linear frequency response with slight boost in the upper midrange and treble
- Great price to performance ratio
- Not a lot of accessories in the package
- Rolled-off bass and lower midrange (not the most linear experience)
- IEMs: KZ AS16, FiiO FA1, FH7
- DAPs: FiiO M11, M6
- DACs: Matrix X-Sabre Pro + X-SPDIF2, Burson Swing & Playmate, Aune S6 PRO
- Headphone Amps: Headamp Gilmore Lite Mk2, Pico Power, Burson Playmate, Erzetich Bacillus