Today I am reviewing the very latest KZ Bluetooth Modular Cable device, the KZ AZ20. I was very happy to receive these Bluetooth ear hooks as I have garnered a decent collection of them over the years and from the promotional material, I see that KZ has added one very good onboard chip. Ya know, I have reviewed quite a few KZ earphones over the past couple years, and I have to be completely honest, they just seem to get better and better. Every iteration of their earphones scales up from its predecessor. So, if KZ takes this same up-scaling theme into their wireless ear hooks then I think we are in for a very well-done set.
I have personally loved the advent of the bluetooth earhook adapters. Doing chores, cutting grass or simply listening to music or watching movies is so cool with them and they get very close to a wired sound. I’ve owned a couple Fiio UTWS3‘s (2-Pin/MMCX) as well as the Fiio UTWS5 (currently the best I’ve heard). I’ve also owned the iBasso CF01 (not recommended) and a few other TRN models that I didn’t care for… Yada Yada. As far as KZ or CCA ear hooks are concerned, I’ve owned or tried a number of their previous bluetooth ear hooks from the original KZ AZ09, the CCA BTX, KZ AZ10 to my personal favorite the KZ AZ09 Pro. Of course, the KZ AZ20 seems primed to jump ahead. So, I think I’m going to cut short the intro and just get into the review, I’m very curious. Without further ado…The KZ AZ20…
-Size & shape is one of the best you’ll find (small and comfortable)
-Brand new QCC5171 chipset
-LEAudio, Aptx-Hd, Aptx Adaptive etc.
-Call quality is better than most with CVC 9.0
-Very stable connection over many hours of use
-Nice macro-dynamics compared to other Bluetooth ear hooks.
-Price against previous KZ earhooks
-Volume level isn’t the highest
-No partnering APP
-No volume controls
-Only fits QDC style 2-Pin (without the mod)
Gear used for testing
The KZ AZ20 arrived at my house in a very utilitarian type of KZ box. Truthfully, I didn’t expect anything elaborate or dolled up as far as the unboxing experience goes. Upon opening the box, you will see the black AZ20 Charging Case which houses the adapters. Also, you get a very short usb-c cable for charging. Nothing really of any great importance here and you get about all you should expect to receive.
Build / Design / Fit / Internals
From a build standpoint, the AZ20 isn’t much different from many of KZ/CCA’s previous wireless earhook adapters. Of course, I also don’t think that KZ had much that needed changing. The build is ultra-light, weighing in at a featherlight 4.9g! I don’t know if any of you have any idea how light that is but let me enlighten you or remind you… the AZ20 feel like nothing on your ear. I’ve said it before and I’ll say it again, the KZ style earhook adapters are clearly the absolute best in terms of ergonomics and to be frank, nothing else even comes close. Please believe me when I say that I’ve tried damn near all of them on the market excluding some higher priced (ridiculously priced) models…cough-cough…Ifi Go Pods. Anyways, the build is a reason to purchase in my opinion.
The main body or “casing” which houses the internal components of the AZ20 is made of a very hard and robust plastic material while the earhooks themselves are flimsier and more malleable and very skinny with a rubber coating covering them. In fact, the Earhooks are so flimsy that you can hear the iems moving around in the case at times. I absolutely adore the build and don’t think KZ needs to change a thing going forward except if they want to add a bigger battery in the future which would obviously increase the casing size. The 2-Pin connectors are setup in a QDC fashion to fit on KZ iems. However, there is a quick and easy modification to allow the AZ20 to fit all 2-pin style iems. Comment below if you want that mod.
As far as looks, I also give the AZ20 huge props for making earhooks which are actually discrete and easy to hide. These won’t get any huge style points, but they are nice. They serve their purpose and also, I don’t think that style points are what anyone is going for here. I’ll say this though, the AZ20 is way better looking than something like the bulky Fiio UTWS3 or UTWS5 just to name a couple. You have the KZ logo imprinted on the casing along with the multi-purpose button in a convenient spot as well. Next to the logo is the light which tells you different operational cues. You’ll notice “L” & “R” are marked on the base of the rubber earhook so not to confuse any hobbyists. All in all, not bad at all.
Due to the ergonomic build, you also have a very nice fit and I cannot help but think that everyone in the known universe should have zero issues with the fit. Of course, that is only true if you are actually a human being… With ears. Having ears certainly helps with the fit, but I digress. The fit is great which stands to reason when you have such a lightweight and soft rubber with what I think is the perfect curl on the earhook. Light as can be, really, I don’t think that KZ could’ve made them lighter than they are. Pair the AZ20 with whatever earphones you’d like with a QDC style. 2-pin connection and you are in business.
Extremely meticulous ergonomic designKZ Promotional
KZ AZ20 boasts an exceptionally meticulous ergonomic design crafted based on extensive research of the human ear contours over the years. The ear hook is made from skin-friendly silicone gel and is pre-molded to ensure a perfect fit. This thoughtful design offers a lightweight and comfortable experience, allowing extended wear without feeling pressure or discomfort. The ear hook fits snugly around the ear contours, ensuring a secure fit that minimizes the risk of the earphones falling off during use.
Internals / Chipset
As far as Internals go, the KZ AZ20 houses the battery as well as the QCC5171 chipset. Friends, I don’t want this to go understated that the QCC5171 chipset is truly one of the absolute best in the market aside from putting in independant amp chips and independent dac chips.
The QCC5171 is an all-in-one solution that truly goes above and beyond the capabilities of regular chips. This chip also offers a gaming mode as well as end-to-end “UWB” Ultra-Wideband Voice. That is a 32khz sampling for smooth voice calls with a very smooth frequency response by basically covering the entire frequency of what us humans can actually hear. It also has much faster encoding for better wireless connections and the power consumption is very low as well, much lower than what we have been used to. However, the best part of Snapdragon Sound is its music playback and the audio Codecs that it supports…
Some of the benefits of an excellent chipset like the QCC5171 is that it offers excellent codec support. This chip just so happens to offer some of the best that wireless audio has to offer. Also, no it doesn’t have LDAC (ldac is a bit overrated) but has something even better in my opinion like LEAudio and Aptx-Lossless which is actual CD-Lossless quality Audio with Snapdragon sound which can output 16bit/44khz bit-to-bit audio. If your phone supports, it of course. However, the AZ20 also has in my opinion one of the best Codecs that money can buy for sheer density and musicality and that is Aptx-Adaptive which supports 24bit/48khz or even 24bit/96khz audio as well as low-latency audio. The AZ20 also supports Aptx-Hd, Aptx, AAC, and SBC Codecs. That’s a mouthful.
Honestly, even if you only use regular Aptx the sound quality is truly great. I promise that very few people can actually hear a difference between Aptx and something like LDAC. The same goes for AAC which IOS users are stuck with. The sound is still very well done anymore, and these Codecs have been really dialed in. I’ve even heard SBC audio that sounds absolutely fantastic. It’s not all about the Codecs friends. I know they want you to think that. Instead look at the technology, drivers, chipset, housing, and tuning. Whether it is tuned completely with an inboard DSP or if there are more traditional methods as well makes a big difference as well. It isn’t the codec, it’s the implementation… Always. Now, it surely doesn’t hurt to tune something amazingly and also have something like LEAudio or Aptx – Lossless.
Controls / Functionality
I’ll be 100% honest, friends, I still don’t know all the controls. I have looked and looked for a list of the AZ20 controls and they are nowhere to be found. I can tell you this, one click answers or hangs up calls, pauses and plays music too. Two clicks on the left is “Previous” track, two clicks on the right is “Next” track. Three clicks on the right is “Performance” Mode and three clicks on the left will cycle between “Bass” mode and “Balanced” mode. Holding down the button will bring up your virtual assistant.
The Charging case is actually very much like earlier versions of the KZ/CCA cases. Same size, same shape, but a slight change in the look and outward design. You still have a very large cavity inside the case to attach any iem that fits the 2-pins. You have some foam inside to protect your earphones as well when bouncing around. However, the best thing about this case is the battery. You get up to 54 hours of battery on this case, which is very large by the way. This thing can last a legit week to week and a half on normal listening. Of course, KZ still has the backwards setup where the left side of the case is for the right side earhook and vice-versa. Not a big deal. The magnets work extremely well so you won’t miss align these very easily. Those magnets catch and they are in place in a snap.
Product Model: KZ AZ20
Bluetooth Version: 5.3
Charging Port: Type-C
Chipset: Qualcomm QCC5171
Bluetooth Range: ~15
Audio Codecs Supported: Aptx Lossless, Aptx-Adaptive, Aptx-Hd, Aptx, AAC, SBC
Signal to noise ratio: 105.1 db
Earphone playing time: ~6 Hrs
Charging Case Battery Capacity: 800mAh
Earhooks Battery Capacity: 35mAh
Extra Charges: 9x
Weight per earhook: 4.9g
Again, this chip allows for Snapdragon Sound. I realize I’ve already explained a bit about Snapdragon Sound but here is a refresher… Snapdragon Sound is an all-encompassing audio solution bringing lossless (bit-to-bit) sound replay as well as an entire infrastructure that allows crazy low latency for movies, videos and games as well as the most robust connection and high-speed connection too. There is a lot more involved but one of the best features is what Snapdragon Sound does for your music through Bluetooth. Truly it is a game changer for music playback.
Bit-to-bit lossless audio is what fans of the technology have been wanting since the beginning. Of course, your phone does have to have support for this. Lossless audio is an exact rendering of the original recording. On top of that, the audio can also scale back its bit rate in heavily RF environments so to never lose connection.
Performance Mode / Low-latency
One great feature of the AZ20 is something that KZ has always used in their wireless tech and that is “Performance Mode” which is basically a low-latency mode. You can get this feature working by simply pushing three times on the left side earhook button. I have to be honest, I’ve barely needed this, but it does help for watching movies and gaming. In fact, one of the greatest joys is watching movies with your favorite iems and there is no delay whatsoever. Now, playing games is a little more up & down as on first person shooters (FPS) it isn’t always perfect but that is only when playing extremely complex games. Furthermore, I don’t think that there is any tws style wireless tech that completely nails latency in complex gaming situations. Every other type of gaming on my phone works like a charm.
Now, please don’t quote me on this because I haven’t gotten any confirmation at all from KZ, though I did reach out. However, just like the AZ09 Pro and KZ’s other Bluetooth earhook adapter models, the AZ20 does also have a gain function in what is advertised as a Bass mode & Balanced mode. The weird thing is that there is absolutely no info that I’ve found telling you how to achieve this. No internet manual pdf, nothing in the advertising, other than that the AZ20 has these functions. So, being that I use the AZ09 Pro every now and again I do know that “High Gain” mode was pushing three times on the left earhook. Coincidentally, when is do this, I do hear a definite gain in volume, dynamics and density of the sound. If I hit the left side three more times the sound does even out a bit so I’m supposing this is what they mean in their advertising as “Bass” & “Balanced”. Again, if you do quote anything I say here make sure to add that I’m not entirely sure. Without question I will update this upon confirmation.
Battery Life is said to be six hours on the earhooks themselves. I have not been able to test this, but I can say that I have yet to run out of battery life and I use the AZ20 every day. Usually when you read a marketing for battery life, they will give you the lowest codec battery life. So, I’m assuming if you listen using SBC codec you will get the full six hours. I could be wrong though as there is no material anywhere to confirm or deny it. Again, using the case you’ll have an additional 54 hours of battery life which is absolutely awesome.
One of the benefits of the inboard chipset is that it allows for Aptx-Voice Technology or Ultra-Wideband Voice support. The AZ20 also has CVC 9.0 on board for crystal clear calls. Friends, I have many meetings through TEAMS in my day job and I spend quite a lot of time in those meetings. Thankfully I’ve been able to use the trusty AZ20 during those calls. All of my partners know what I will ask of them before the meeting takes place… “Guys, be honest, tell me exactly how I sound!”. All I heard was good stuff about the AZ20 from both the people I work with as well as my wife.
I will keep this portion brief because there is only so much you can say from a source such as this, but I will try my best at giving you a good rendition of my time spent with the AZ20. Please trust me that I’ve spent a few straight weeks with these adapters. I spent most of my time using KZ iems due to the QDC style 2-Pin. Primarily I used the KZ Krila due to the fact that the KZ AZ20 is not the most powerful earhook adapter (much like most earhook adapters) and performs much better with very sensitive iems. I would have performed the modification to the 2-Pin but wanted to make sure I review this unit “As-Is” out of the box.
To begin the “Sound” portion of the review I find the AZ20 to be close to warm/neutral and relatively dynamic so long as you use the gain function by pushing three times on the left side button. Compared to the AZ09 Pro, the AZ20 has more density to the sound with a seemingly wider frequency range. I feel the AZ20 has a boost in overall macro dynamics as well as control.
Between the 20’s
As far as what you’ll hear in between the 20’s; the bass is nicely present as I hear some slight low-end coloration with a small boost down low to make things interesting. I love that the AZ20 gave the Krila some nice sub-bass boost and gave the Duo some needed rumble as well. The midrange doesn’t sound too laid back or too forward. If anything, the mids are a bit more pronounced which makes a set like the Krila very pleasing for vocals. The treble is not overcompensated and doesn’t offer any sibilance. At least nothing greater than any earphones’ natural proclivity towards it (sibilance). Meaning, the AZ20 won’t add any more sibilance. The treble has a decent bite up top and gives some levity to the mix. Especially with warmer sets.
The soundstage is whatever your earphones will give you and doesn’t really come from the AZ20, but I could attach that to anything I state here. In truth, all the AZ20 can do is further color (or not) the sound and add dynamics (or not). However, one thing the AZ20 does over something like the AZ09 Pro is draw out the subtleties and nuances within a track much better. Detail retrieval is actually a step up without losing focus on sound density and dynamics. KZ is getting closer to that “wired” type sound with these Earhooks. Again, imaging is as good as your earphones but there is some persuasion from the Earhooks. Let’s put it this way, the AZ20 doesn’t make any earphone worse in this sense.
Downsides to the sound
I actually completely enjoy these lil baddies. They are very nice, and the sound is fantastic. However, there are some issues that I have. For one, KZ… why is the volume so low? I tried using the KZ AZ20 on a few different sources like my iPad, my wife’s phone, my Samsung Galaxy Fold 4 and my daps and on each the volume just made it to acceptable levels. We want headroom! Pump these things up! I want to have to turn these down because they are too damn loud. That said, this does make me question the Drivability of the AZ20. Now, I didn’t have an issue with any set I used as far as how well the AZ20 can drive them. Still, I honestly have to max these out to get a good sound level. I will also add that I like to listen pretty loud.
Another issue is not an issue with the sound itself but with the experience when listening to my music as there is no way to turn up or down the volume from the earhooks. In this day and age, we shouldn’t leave this simple function out. Of course, I’m sure that not many will be too bothered by this as these are the only true downsides for casually listening to music that I can think of.
KZ AZ09 Pro ($40-$45)
The AZ09 Pro I’ve mentioned a few times in this review, and I’ll tell you all something… For the price that set is hard to beat. It does everything that the AZ20 does, but the sound quality takes a slight hit. As far as the intangibles like connection, call quality, and different modes of operation I can tell you straight up that the AZ20 eclipses the AZ09 Pro handily when comparing connection speed and strength of connection. I lose signal with the AZ09 Pro every now and again and it isn’t a big deal because they are so cheap. I deal with it and reconnect. However, for $88 the AZ20 better have no issue at all, and I can absolutely say that the connection is rock solid. Everything else is darn near identical. All functions are just about the same.
Now, battery life on the AZ09 Pro gets you about an hour more of playback but 8 hours less with the case so I think that’s a trade-off unless you actually keep these things in your ears that long… I feel bad for your ears if you do. Anyways, the AZ09 Pro only carries Aptx, AAC & SBC rather than the ultra-Hd audio Codecs that the AZ20 gets you. Also, the chipset is a downgrade on the AZ09 Pro with its QCC3040 chipset from the QCC5171 chipset of the AZ20. Granted, the 3040 is a tried-n-true chipset which is very well established. However, it is still a downgrade.
Speaking of sound, the sound is a bit leaner on the AZ09 Pro and you don’t have that density and note weight of the AZ20. The AZ20 also has the more impactful bass, lusher mids and more sprightly treble. Honestly, it all comes down to sheer macro-dynamics and I can tell you that the AZ20 is truly an upgrade in that regard. The sound is cleaner with less floor noise and better transient attack & decay. The AZ20 really does hit the mark in the sound quality department in ways that the AZ09 Pro cannot. No doubt about it. There is one thing about the AZ09 Pro that it outduels the AZ20 and that is in volume level. I can get the AZ09 Pro slightly louder. However, the sound quality and fidelity aren’t as good, so it is a moot point.
In the end
This is simple, how much do you want to spend? Costing about twice as much as the AZ09 Pro, the AZ20 in my opinion is twice as good. Of course, I’ll pay for incremental differences in sound and fidelity. It may not mean as much for you. You may only want this set for phone meetings or to watch movies and in that case, I’d probably go with the less expensive set. Still, in the end, the AZ20 is certainly the more audibly proficient and sonically gifted earhook with a more visceral and vibrant sound as well as a much better connection.
Fiio UTWS3 ($59)
This is where the AZ20 may begin to find some issues? Or will it? On paper the UTWS3 should be the better set as far as sound quality goes with its independant amp section and greater power. Much greater power (I’ll cover that in a minute). There are some huge discrepancies though. The UTWS3 came out a few years ago now (believe it or not) and the chipset is very much outdated and old as they use the QCC3020 chip. The thing I find the most troubling about the UTWS3 is the connection reliability. Please trust me, the UTWS3 drops connection quite a lot. Too much for a wireless device and will only end up upsetting you in the end. Also, the UTWS3 does weird things like; not recognize when you put it in the case. Or not turn off, or just randomly turn on and use your phone’s bluetooth… while the UTWS3 is in the case! So, as far as intangibles… Fiio ain’t got nuthin’ on the AZ20.
The first thing I noticed when comparing the sound is the obvious power difference between the two. The Fiio UTWS3 is most certainly able to drive slightly harder to drive iems a bit better. This is not world changing but there is a difference. The UTWS3 has headroom. Maybe not like its big brother the UTWS5 but… It has some juice.
The next thing I noticed was, the UTWS3 has more warmth and comes across less crystalline and clean. The AZ20 has the more transient quick and detail-oriented playback which seems airier whereas the UTWS3 is a bit more bass present but also a hint less resolute. These are very minimal differences here. That said, the UTWS3 is also the more fun sound, bigger low-end, better extension in the highs (up for debate) and simply the more dynamic presentation. This is not to say that the AZ20 doesn’t have a nice low-end because it certainly does. In fact, I’d say the low-end is cleaner on the AZ20, slightly less in quantity but better separated, more mature and hardly less dynamic. The AZ20 midrange is better to me with more forward mids which retain some lushness with great presence for vocals while the UTWS3 is all lush and less technical. Between the two, I do prefer the AZ20 because the sound is more resolving with a more technically adept sound that still holds onto some nice dynamics but also has a better dynamic range.
In the end
Honestly, unless you have some mmcx iems you want to use, or you hate modifying things and cannot spend over $60 then I’d say the clear winner here is the AZ20… ALL DAY. Just a better set. Maybe not as rich in density and lush vibrance but the AZ20 has better dynamic contrast and is simply airier with a more convincing replication of a wired sound. It’s the dynamic range in comparison and the note definition within that range that larks a difference. Or the punchiness and tactility of each note rather than the UTWS3’s softer and more fuzzy note definition. However, you have to get what works for you. The AZ20 has a top-of-the-line chipset that is at the cutting edge of what one should be able to get under $100. Of course, I wish that the AZ20 had more power. Still, if you have sensitive iems then the AZ20 is nice folks.
Is it worth the asking price?
This is a good question. I suppose for some folks the AZ20 and all its benefits wouldn’t be needed, and they could quite happily rely on earlier versions of KZ earhooks. For some the AZ20 won’t have enough functions to justify the price. It all comes down to your own particular situation I suppose. What I do know is that KZ created the AZ20 to sound good, fit good, and function good, and in my humble opinion they succeeded with those, and I don’t think many people would argue against that.
They do lack some bells and whistles compared to many of today’s wireless devices. In the same breath, does anyone here really need ANC or wireless charging, ambient mode… etc? I can make pretty solid arguments both ways but at the end of the day everything will always boil down to your own specific needs and even more so… your wants. Speaking for myself, I don’t need the gimmick that is ANC or ambient mode and I never use wireless charging and so I don’t find those things necessary or even beneficial to me. Still, I’m not you.
Speaking only for myself… I thought $88 was a bit steep at first. The reason is because I’ve actually purchased many earlier versions of KZ/CCA earhook adapters which were always under $50. As you can see $88 is a large price jump. It wasn’t until I found out what chipset they were using that I understood. Folks, KZ went for the “crème de la crème” as far as Bluetooth chipsets goes and honestly, you can hear it and feel it with the great sound and ease of use.
On top of that, the AZ20 are the best fitting and most comfortable earhooks that I know of. I really believe that. The build and design are such that they feel like nothing on the ear. Reception and quality for calls is fantastic, the wireless connection is truly flawless. However, the real reason is of course the sound. The AZ20 is simply clean for a wireless device, trumping the top tier earhooks from only a couple years ago and quite easily outclassing the lesser expensive earhook adapters.
Also, the AZ20 earhook adapters are just… easy. Everything works as intended, they are easy to use across the board and when I look at these adapters as a whole, I’d say that yes, the AZ20 are certainly worth the asking price providing they make sense for your life.
Now, that is a loaded statement, I realize this. I also own the Fiio UTWS5 which is better in almost every regard besides fitment, of course it’s also $40 more in price. So, for my particular situation is it worth paying $88 for the KZ AZ20… Probably not. Unless I have money to burn, which I don’t. Maybe I’ll say it in another way… In a hypothetical world, if I didn’t have any other devices I would without question find the AZ20 the perfect device to purchase, probably over all others. I do think it’s that much better than past KZ/CCA earhook adapters as well as other models from other companies. At least from those that I’ve actually used. KZ did a nice job on these folks.
Note: I want to preface this section with a few thoughts. All ratings are based upon my subjective judgment. These ratings are garnered against either similarly priced sets or with similar driver implementations or styles with the unique parameters of my choosing. I don’t really feel ratings are the best way to distinguish how good or not a device is. Ratings leave out nuance and don’t tell the story of how anything truly performs. These particular ratings of the KZ AZ20 will be garnered against other earhook adapters ranging from $30 to $100. This is actually a very small pool of devices believe it or not and so seeing a Rating like “9” shouldn’t surprise anyone. Also, a “5” is exactly average. My ratings are never the same and each set of ratings tells a different story. Each time you read one of my ratings it will be unique to that review. Basically, I create a Rating that makes sense to me.
Functions & Features
-Feature Function: 9.7
I did not enjoy Rating these earhook adapters… At All. I find it extremely difficult to do so. There is so much nuance and intangible little pieces to the puzzle which gets left out by simply seeing a “9.5” overall sound rating. Quite literally I could argue against almost every Rating I established above… to a degree. This also took me a very long time because I don’t like slapping a number of things. However, ratings can have their place and be helpful, but I just remember that a lot is missing in simple number ratings.
The only portion of ratings I’m truly happy with is the “Aesthetic” category. I feel good about those. Eh, the “Sound” ratings are pretty cut and dry as well but there are some questions there too. I suppose the real issue comes down to this; by what standard do I derive these ratings, other than my own subjective judgment? Secondly, how am I to think that anyone else thinks as I do. Not everyone owns my same gear, has heard what I’ve heard and likes what I like. Basically, try to remember that these are simply my ratings that I made for my purposes and against those devices that I’ve heard and used. I do hope they help. All things considered; I think I got them right to the best of my ability.
To conclude my full written review of the KZ AZ20 I have to say that I have been very impressed with this set of earhooks. I will continue to use them daily as they have been a perfect case of “ease of use” and convenience. I really truly think they are fantastic. With that, I want to thank KZ as well as Tyvan Lam for providing the KZ AZ20 in exchange for a feature at Mobileaudiophile.com and some exposure of their product. Thank you very much.
I also want to urge you all to please pursue other thoughts of the AZ20. I am only me and not everyone thinks as I do, has the same likes and dislikes, hearing abilities and not everyone has been down the same journey through audio as I have. So please check out other perspectives before spending your hard-earned money on anything I review. Remember, the point is to help you all get these decisions right. Well, and because writing these reviews are 100% therapeutic and an awesome creative outlet. Thank you for reading, take care, stay safe and as always… God Bless.