Hidizs AP200 - Reviews
Pros: Great neutral sound signature with emphasis on the upper midrange and highs.
Cons: Awkward bulk and form factor when used daily. Laggy User Interface despite being a year old device. Leather case is a burden to use.


“Experience Music like never before”, Hidizs’s marketing slogan should be considered in relevance to their current flagship DAP (Digital Audio Player), the Hidizs AP200. With the influx of audio players being a common sight nowadays, that’s a bold statement to uphold. Let’s dive in deep and see if this mid-tier player provides an experience like never before.​

The Hidizs AP200 that we would be realviewing was purchased independently so no affiliation and influence from Hidizs whatsoever would impact this realview. Hidizs was founded in 2009 and released their 1st music player way back 2014, the AP100, roughly 3 years after, the supposed successor for the latter was released in September 2017, the AP200 (this should be 100 times better, right?) which initially started as a Kickstarter project resulting to 943 backers which successfully received their respective AP200’s. The Ap200 was able to secure JAS (Japan Audio Association) and CEA (Consumer Technology Association) certification to ensure a high-quality sound device inside and out, priced at USD $299 for the 32gb and USD $399 for the 64gb, it targets the heavily contested mid-tier audio player market.

Specifications and Packaging

Offered in both Aluminum Alloy body in Silver, Black and Blue hues and Stainless-Steel body with multiple rear panel options including Glass, Rosewood and Carbon Fiber, aesthetics was indeed taken into account by Hidizs to cater the mid-tier market. I opted to get the 64gb Stainless steel Carbon Fiber weighing at roughly .46 lbs or 210grams to compliment my trusty pseudo steel finish Acer Aspire F15. Driven by Quad core Rockchip 3188 processor, 1gb of RAM in a deeply customized Android 5.1.1 utilizing Dual ES9118C DACs and the TPA6120A2 AMP chip, on paper this should feel similar to our old flagship android user experience way back 2015 with emphasis on audio, similar to the LG v20’s target market a year ago.

Package in all matte box embossed with the Hidizs branding and model number upfront with the backside adorned in silver lettering spec sheet. The sides would show the serial number as well. This would sit well on our shelves for the box fetish in us. Lifting the cover would immediately reveal the player with a pre-installed screen protector which wasn’t applied really well and showed bubbles underneath, they should have done a better job here although a spare is provided. Inside one would find the AP200 case, USB Type C cable, warranty card and user manual.

Build quality, User Interface and Handling
Right of the box and grasping the player, the 1st thing that comes to my mind is that this is THICK! The typical stainless-steel feel is evident and the form factor coupled with the build material makes one to be feeling like holding a gym barbell, this might be good for some which would assure you that this is built sturdy yet when I was using it regularly, it is already hefty enough for my khaki and denim pockets.

One hand use is great attributing to the 3.5-inch display that is not visible enough at max brightness when used outdoors but decent enough during indoor morning sessions at work with office lights all turned on. I carefully checked for body scratches and nicks and none were found right off the box and being used for almost a month now, only hairline scratches on the mirror back were observed.

The left side play/pause and volume up and down buttons have great click responses although when using the included plastic clear case, the accessibility and ease of usage of these physical buttons fall drastically. The plastic clear case is the way to go over the Hidizs ap200 leather case which I purchased separately, it is nowhere easy to use and the cut outs of the leather case which was made to be inserted from the bottom made it very hard when using the power on and off button for turning off the display when in use as it slides the leather case down thus disorienting the whole display and physical side buttons and one would need to push it back up again, a waste of leather case materials and consumer expenses, I personally just use it for looks now. The latest firmware being 0.2.8Beta was installed and used for the duration of the realview and overall it was better than the initial firmware used on the ap200, the UI is more responsive in comparison to the initial firmware. Note that this is 1st a music player but since it has the Android playstore, I decided to install the usual suspect applications Youtube and Facebook and boom, one word, DON’T.
This player is not a phone it would take around 2 to 3 minutes before one would finish typing any username along with the @gmail.com, password and keywords before you get what you want off Youtube and Facebook. Spotify was then installed and used to stream regularly, no software issues were encountered. Accessing the settings page is easy and all the necessary options are there along with in-line remote option which surprisingly my Fiio F5 with inline Mic doesn’t work. The gold shielded 3.5mm jack is built like a tank and should be commended, I think this would last longer than most average players except Sony along with the Type C connection as it blends well with all my devices, it’s great when a single Type C cable handles all our gears, right? Overall the build quality of the device is great yet the weight might turn off some, the handling is not your best buddy either as well as the UI though it would suffice for daily usage for a user who just let his whole playlist run through its course.

Sound Quality and Battery Life
Dual crystal oscillators and gold-plated Dual ES911C DAC chips that supports almost all music files an audiophile nowadays uses from FLAC, APE, WMA, WAV, ALAC, Apple LOSSLESS, DSF, and DSDIFF and Native support for DSD 64/128, PCM up to 384Khz/32bit, this mid-tier player got you covered. Bluetooth 4.0 and Apt-X support is there as well, those wanting LDAC and Apt-X HD might need to wait for the ap300 if it would ever come. I opted to fill up the 64gb internal memory 1st with FLAC and DSD files with some mp3’s for fun and conduct my realview off there. The Sony Cd900st with Yaxi pads stpad2, Koss Porta pro with Yaxi pads, Kinera Seed with H3 cable, Fiio f5, Audio Technica AD900x and Black Bud Red were used in the realview, I will mention which gear and track was used on each observation. I tried the Black Bud Red, a 32-ohm bud from Good Sound Gadget, this exhibits warm with great clarity for its price signature, using the DeadPool OST Album in FLAC, Ashes was presented calmly with the sub bass resonating all over the song yet Celine’s voice still climbs above, Nobody Speak guitar plucks was crisp and DJ Shadow’s rap was laid back, each rap outro didn’t exhibit excellent thump. All out of Love’s guitar plucks was still crisp yet the sub bass here is more controlled. Next up is the Koss Porta Pro with Yaxi pads, note that this can exhibits bass heavy signature with great control and couple with the Yaxi pads, sub bass is further refined. Ashes was still presented calmly and now the sub bass wasn’t resonating anymore and Celine’s voice has more body and clarity. Nobody Speak guitar plucks are still crisp and DJ Shadow’s rap is a wee bit clearer yet rap outro still has shallow thumps. All out of love’s guitar plucks are still crisp and sub bass controlled as well but the vocals are more airy, ample Air Supply maybe? Next up is the Fiio F5, I’m personally not a fan of this for its warm signature yet it has its own place for that particular characteristic, warmth. Norah Jones’s Don’t Know Why opened up great, imaging was noticeable albeit intimate, separation was delivered well too and Norah sang clear and lush while each opening note when she begins each stanza, vocal extension is greatly observed. Come Away with Me was subtle and detailed, Norah’s vocals here are airy and sparkle is to be found, I normally hate the f5 for not being able to at least showcase this. I finally pulled out the cans, 1st up is the Sony cd900st, a classic in its own right due to its reference sound, it does lack punch yet has ample punch on the low end. The ap200 easily drives this, identical tracks were used and the vocals here are clearly highlighted, mids and highs are very detailed, separation and imaging are clean and mimics a small conference room, clarity of different instruments distinct sound are distinguishable. The ATH AD900x was also driven quite well by the ap200, staging and imaging right off the bat are the noticeable improvements compared to the cd900st, the midrange is similar with the ad900x cutting more into the top-end with its near sibilant ability. The bass aspects were nowhere special. I both toggled between the High and Low gains throughout and preferred to keep it on High 90% of the time. Navigation of the Hidizs player powered by Hiby was decent considering my stubby fingers coupled with the occasional hiccups of the software itself. I tried to tinker with the ap200’s Low Pass filter options and after sometime, I opted to keep it at “Brick Wall” although personally each option was barely noticeable with each toggle. Bluetooth pairing was done with the Sony CAS-1 system and it was a delight, no stutters whatsoever except when the music software stutters on itself. Battery Life was great since considering it is under Android’s umbrella, FLAC usage in pure music mode yielded around 7 hours of playback with 3 to 5 pauses ranging from 5 to 7-minute intervals. DSD in music mode came at around 5.5 hours. Volume output was at 65-80/100 95% of the time. Android mode with Spotify streaming in Extreme quality came at around 5.5 hours. I personally didn’t check Hidizs advertised battery life so feel free to check it out yourself and find out for yourself.


The Hidizs ap200 targeted the mid-tier market with emphasis on “Experience Music like never before”. It is a well-built device and has variety of aesthetic options. The weight is a double edge sword as well as its compactness. The leather case is a big NO and not a lot of 3rd party case options makes one to settle in the plastic clear case provided. Software and User Interface experience is acceptable at best and for a device already out in the market for a year, this is its biggest weakness. If by some case anyone from Hidizs reads this, we hope they take care of their software now more than ever with successive releases of entry level music players by the company, building a dedicated fanbase is crucial and from the social platforms managed by Hidizs, things are not looking great. The materials used are awesome, the use of the gold shielded 3.5mm is commended specially that it was released at a time when a noted music player it was compared to got its 3.5mm jack questioned (guess the player? it’s named N**). I wished this had balanced out since single ended use was great. The strength of this music player is in its sound. Based on my listening sessions, it clearly shows a fairly balanced signature with emphasis on the top end which paired great with warm earphones complimenting what it lacks and at a decent volume output, bright sound signature gears will be shine with this player. Did it hit the “Experience Music like never before” slogan? As much as I find its sound and synergy with most of my gears interesting, this player will be in the used market sooner than later without a feeling of longing.
Pros: •compact design
•clean sound
•really good hiss performance with very sensitive IEMs
•good UI and Hiby Player (although without track counter on playback screen)
Cons: •output impedance on the high side for in-ears that don't have a flat impedance response
•promised USB DAC Output feature doesn't work well yet; promised update deadlines weren't met
•as some other streaming DACs, there can be some occasional 2.4 GHz WiFi interference noise, depending on your environment
This review was prepared, written and mostly finished several months ago, but there were delays. But here it is now:


Arbeitstitel: “Der Anti-AP60”/”Ziegenpeter”/”Fräulein Rottenmeier”


Hallo zusamm’n! / Hallo zusamm’n! / Hidizs, Hidizs, / deine Welt ist die Musik. / Hidizs, Hidizs, / denn du spielst sie auch aus der Cloud. / Bluetooth, Wi-Fi / und zwei ESS SABRE-Chips, / Hidizs, Hidizs, / bietest du uns jetzt an.

„Hidizs“ ist die rührende Geschichte eines jungen digitalen Audio-Spielers, der von seiner Tante DT (1350 Pro) zu einem Hi-Fi-liebenden Einsiedler gebracht wird, bei dem er fortan leben soll. Dort lernt er unter anderem Peter Herbolzheimer kennen, der den Katzenfisch hüten muss, und freundet sich mit ihm an.
Doch eines Tages bringt Tante DT (1350 Pro) den Hidizs zu HiFiMan in Frankfurt, wo er unter anderem zusammen mit HiFiMans physisch eingeschränkter Tochter RE2000 lernen soll, sich mit dem Internet und Bluetooth-Geräten zu verbinden, woraus sich schließlich eine gute Freundschaft entwickelt…

- - -

Wie auch immer…
Man kontaktierte mich und fragte mich, ob ich den AP200 testen und rezensieren wolle. Ja, warum denn eigentlich nicht. Obwohl man mich zuvor seitens Hidizs fast immer ignoriert hatte, was ich definitiv nicht vergessen habe oder werde, willigte ich ein, da ich den AP200 optisch sehr ansprechend fand und dies noch immer tue.

Ob der AP200 genauso scheiße suboptimal als vollwertiger Standalone-Audio-Spieler wie bereits der vor längerer Zeit rezensierte AP60 ist, klärt diese englischsprachige Rezension. Manche der technischen Daten deuten teilweise leider darauf hin – doch dürfte der AP200 dem AP60 meilenweit voraus sein, was die Bedienung betrifft. Auch besitzt er mehr Funktionen (bspw. Android und Wi-Fi). Dementsprechend könnte sich der Streaming-Player AP200 womöglich tatsächlich (sehr gut) als kompaktes, digitales Quellgerät zum Anschluss an einen externen DAC, oder als digitaler Audio-Spieler für unkritische In-Ears und Bügelkopfhörer eignen.



Honest words: Personally, I think that the original Hidizs AP60 sucks, even for a clearly budget-oriented device. There are cheaper audio players with clearly superior unloaded and loaded audio performance and measurements than it, its navigation and operation with the touch button control is quite useless and imprecise, especially on the go, and it only really serves a purpose as a digital source for aptX Bluetooth streaming and as a digital transport source for an external USB DAC (this is what it really does well though). Yes, those are the only two scenarios where it makes sense as a product, and fails in most others if you have standards that are higher than a monkey’s or those of non-audio people.


Anyway: The Hidizs AP200 on the other hand appears to be so much more promising – judged by its audio specs, probably not as the ideal standalone music player for super sensitive multi-BA in-ears with an uneven impedance response, but certainly as a proper source for most full-sized headphones or dynamic driver in-ears with a lesser impedance swing, and as a great digital music and Wi-Fi as well as aptX Bluetooth streaming source for wireless headphones/in-ears and external DACs. Yes, this is a scenario where the compact and reasonably priced as well as feature-packed (dual ES9118C SABRE DACs, Wi-Fi, hi-res IPS touchscreen, aptX Bluetooth streamer and receiver, digital USB output and input, …) AP200 could turn out to be a good choice.
Will it?

Full disclosure:
I was contacted by Hidizs regarding the opportunity to receive a free sample of the AP200 for the purpose of honest testing and a review. I agreed and then received a sample at no cost, without any other obligations or requirements.


Price: from $299

Hidizs AP200 Technical Specs.jpg
Source: http://www.hidizs.com/product_ap200.php

Unboxing & Delivery Content:

The black cardboard box the player arrives in is quite plain and standard.


Inside, one will find the player with a screen protector for the back and front already applied, a plastic bag with some spare screen protectors, a USB cable for PC data connection and charging, a USB cable for DAC connection, and last but not least a plastic protection case.

Design, Feels & Build Quality:

The AP200 is available with different designs/finishes and amount of internal memory. I received the black version with 32 GB of built-in memory.
What makes the AP200 probably more interesting than a modern smartphone as a streaming source is that it is more compact and outdoor-/on-the-go-friendly than those, and that it has got more volume steps and a superior hiss performance than most (more on that later).

The brushed, CNC-milled chassis looks elegant and clean, and one can definitely see Hidizs’ new design language that started with the AP60 being continued with the AP200, however the AP200 has got the massive advantage of utilising a real touch screen unlike the AP60 that uses tiny touch buttons for navigation.
Yep, it’s a still rather compact, well-built, quite beautifully designed digital audio player.


Not really big criticism, but since the back panel consists of glass as well, it is quite a fingerprint and dust magnet. And I’m personally not really a fan of the included protective plastic case, even though it works just the way it should.
Speaking of included accessories, it is nice to see an OTG cable to use the player with an external DAC bundled, however it’s not so nice that that very cable is really not as flexible as it could or should be for portable stacking use – but it is still better than no included cable.

Anyway, the AP200 has got four buttons – an on/off button located at the top, a circular play/pause button located at the left side, and also two volume buttons (that also act as skipping buttons) on the left side as well.
At the bottom, we can find a 3.5 mm headphone output, one micro SD slot, and last but not least a USB-C socket. Just like the iBasso DX90, the AP 200 lacks a balanced headphone output despite having a balanced dual-mono internal audio circuit implementation (personally, I don’t mind it though and also don’t need it). It doesn’t have any line or digital outputs either, except for a digital USB output to use it with an external DAC, and this socket also serves as a USB input to use the Hidizs as a USB DAC on a PC.

The Screen:

The IPS touchscreen measures 3.54 inches with a resolution of 960 x 640 pixels (325 ppi). Thanks to this, images are crisp and viewing angles are stable, however please don’t expect the maximum brightness to be really bright since it just isn’t.
Colour reproduction and contrast are good, but not fully on the same level the best currently available devices although they come nicely close. It’s good to see though that they didn’t go for an oversaturated, over-sharpened screen with extreme contrast settings, and colours are just slightly on the warmer side.
Since it is a multi-touch touchscreen, it also recognises multi-touch gestures if supported by the app. The responsiveness of touch inputs is very good and without any delay.

Volume Control:

Volume is controlled via the two buttons on the left side or through the touchscreen once you have pressed one of the two buttons. Quick volume attenuation can then be done by swiping from the top to the bottom of the screen (or vice versa) once that popup shows up.


There are two gain settings and 100 system-wide volume steps in Android and pure music mode, which I find somewhat too few given that the DAC allows for 256 steps that would give you even more precision when trying to find the right volume setting without having the feeling that an additional step between two steps would be required for that. However, which is good, listening at very quiet levels is still possible with extremely sensitive in-ears.

What’s quite neat though is that the AP200 supports in-line remote control commands (well, play/pause at least, but volume button commands don’t seem to be supported).
What is a bit annoying though is that a fast double-click of the volume buttons skips the track.

Operation, User Interface:

The AP200, just like the iBasso DX200, is a player that actually comes with two operating systems – Android 5 and Hidiz’s pure music mode firmware. Well, this isn’t entirely true since the latter isn’t really a separate operating system on the Hidizs but basically just the stock Hiby player app being made sticky. It can be accessed through the drop-down notifications menu.

Android OS, Player Firmware Version “0.2.2Beta”:

The AP200 is running on Android 5 OS, so you don’t get an old looking or outdated system but a still modern one that is also up-to-date for most recent apps.
And what is great is that Hidizs has kept the Android system quite stock with just a few audio-related changes being made to the drop-down notifications menu, and what’s really great as well, or let’s face it, even greater, is that the AP200 comes with the Google Play Store, so you can easily download all Android apps that you are familiar with and can of course also easily install and use third-party music player apps. Great!

20180111_200503.jpg 20180112_061425.jpg

The stock player app is a Hidizs-customised version of the Hiby player, and its interface is modern and quite intuitive.


There are basically three screens – the settings, the library and the music playback screen. In the settings, one can use the AP200 as a network streamer, enable a 10-band EQ or change the DSD and folder playback settings. The other audio settings such as the gain and audio filters can be accessed through the drop-down notifications menu.

20180111_201017.jpg 20180112_061442.jpg

The music library contains categories such as “All”, “Album”, “Playlist”, “Artist”, “Folder”, “Genre” and also network folders. It has also got a proper on-screen-keyboard search feature that I think is mandatory to have on a modern audio device.

20180111_200843.jpg 20180111_200902.jpg 20180111_201125.jpg

The music playback screen is quite simple – it shows a large album artwork, title and artist information, the sampling rate, and other playback information such as the time and a button to change the playback mode and another one to add the currently played file to a playlist. There are also virtual play/pause/skip buttons.
Other than that, the normal Android status bar with the battery percentage, time and volume info is displayed as well. Tapping on the album artwork, one can display the track lyrics (if available and stored in the music file).
What I’m however missing is a track counter.

20180111_200950.jpg 20180111_201402.jpg

Pure Music Mode, Player Firmware Version “0.2.2Beta”:

Pure Music Mode is actually no dedicated OS but the Hidizs-customised Hiby player App being made sticky. It really is the same, and I honestly don’t really see the point of it.

- - -

Overall the firmware is also pretty stable, without any playback errors so far and only occasional crashes and random reboots when connecting external DACs to the AP200 or when opening third-party apps – so this is a thing that could and should be improved and fixed in the near future, since even though this behaviour is occasional, it can be annoying if it happens and you have to wait for the player to reboot.


Built into the AP200 is a quad-core CPU (Cortex A9, 1.4 GHz) with 1 GB of RAM. It is plenty fast (scanning the music library only takes little time, animations are fluid, responsiveness is good, opening and closing apps works fast and fluently, too), and booting takes ca. 32 seconds.


WiFi signal strength is good as well and comparable to my Asus Google Nexus 7 (2nd generation) and Acer laptop. WiFi speed is somewhat slower on the Hidizs though.
The only downside is that the AP200 “only” supports 802.11 b/g/n 2.4 GHz WiFi, and just like the DX200 in 2.4 GHz WiFi mode, the AP200 might occasionally output some WiFi interference through the headphone output into sensitive headphones/in-ears if some other WiFi sources are close to it, which is a bit sad. This also seems to depend on the location and environment, since I get that interference with all digital audio players with WiFi (apart from my Apple iPhone 4) on my 2.4 GHz router. (So yeah, smartphone manufacturers get this right while apparently many digital streaming audio players exhibit noise when connected to a 2.4 GHz network.)

20180111_200706.jpg 20180112_123705.jpg

- - -

To test the CPU performance further, I ran a CPU benchmark tests (Geekbench) on it and compared it to my Nexus 7, a tablet computer that is still more than plenty quick, fluent and doesn’t really struggle with anything.



Asus Nexus 7 (2nd generation)

iBasso DX200

Hidizs AP200

Single-Core Benchmark:




Multi-Core Benchmark:




I think the result speaks for itself and shows that hardware-wise, the AP200 is a potent and capable device that should not struggle with running any supported music app and apps in general.

Battery Life:

Ultimately, the battery life will of course depend on how one is using the AP200 (headphones, volume setting, file type, WiFi, Bluetooth, …). Since it has so many features, the battery life you can get might be shorter or longer than what I got in my non-representative test that I did to see how much battery life I could get when mainly playing FLAC files and streaming some music for around 90 minutes while occasionally unlocking the screen and navigating through the menus.
Using the inexpensive Superlux HD668B as a load at volume 50 out of 100 (low gain), I was able to get almost 8 hours and 30 minutes from the AP200 under these test just-mentioned environment conditions (Hidizs claim around 8 to 10 hours, so I can definitely back this up now. Without using WiFi, coming closer to 10 hours is definitely possible).



Frequency Response, Output Impedance:

One of the most basic and fundamental things an audio player should have is a flat unloaded frequency response in the important range of 20 to 20000 Hz. While it is anything but sorcery to achieve this in modern days, some (however mainly inexpensive and rather no-name) audio players still fail to achieve this basic thing.


Let’s see how the AP200 performs in this regard (measured with Digital Filter #1):

no load #1.jpg

As it could be expected and unlike the AP60, the raw and unloaded frequency response of the AP200 is perfectly flat and therefore just the way it should be.

- - -

Even when having a flat frequency response without load or with a simple load (such as a headphone that has got the same impedance over its entire frequency response), things are getting much more difficult with most multi-driver in-ears that have got more than just one driver and a crossover circuit that causes the in-ears’ resistance to vary along with their frequency response.

If the audio player’s headphone output doesn’t have a low output impedance, the in-ears’ frequency response and therefore heard tonality will be skewed and they will (depending on the player’s output impedance and the in-ears’ specific impedance response) sound more or less different than when driven by an audio player that has got a low output impedance.
To maintain an unaltered sound even with low impedance multi-driver in-ears, it is therefore best to have an audio player that has got an output impedance of less than 1 Ohm.

This is what the AP200 puts out when connecting a critical, low impedance, multi-driver in-ear to its single-ended output:


The connected load was my Ultimate Ears Triple.Fi 10, an in-ear that is among the most source-picky species of its kind and changes its sound rapidly as the player’s output impedance climbs.
The measured deviation when connected to the AP200 can be calculated to be slightly below around 7 Ohms (the officially claimed value is ca. 4.8 Ohms), which is unfortunately very plausible given that the actual output impedance of the AP60 was also already higher than the claimed spec.
So unfortunately the AP200 is not multi-BA in-ear-friendly and would audibly change the sound signature of such in-ears that don’t have a ruler-flat impedance response. Pity.
Therefore this is a digital audio player for (most) dynamic driver in-ears and higher-impedance full-sized headphones (or lower-impedance full-sized headphones if their impedance response is flat).

The 7 Digital Filters:

The AP200’s ES9118C DACs have 7 digital filters incorporated that the user can choose from.
What digital filters mainly do is shaping the upper end of the frequency response as well as the impulse response, which could be perceived in a subtle difference in the treble and soundstage reproduction but is inaudible in most cases as long as the filter does not affect the upper frequency range by too much.


I will definitely not go into detail about what the filters do exactly and how this affects the frequency response as well as pre- and post-ringing of a signal since this would just exceed the frame of the review (that is probably overly long anyway) by a bit too much and because there are a couple of informative websites and contributions about this topic on the internet. So instead, I will show you how the filters affect the frequency response from 20 to ~ 18.5 kHz (because this is the range where my soundcard’s input response measures flat). After that, I will briefly describe what differences I can hear, what I cannot hear and how distinct I find the effect.

So here are the 7 filters:


Filter #1 is the one that is the most commonly used in audio applications and selected as standard. All of the other filters interestingly measure identically from 20 to 20000 Hz when it comes to pure frequency response. All of the other RMAA measurements apart from the stereo crosstalk are also basically similar between the filters #2 to #7. I couldn’t/didn’t measure the impulse response, which is the area where the various filters would differ.

The question is – do these filters really have a greater audible effect that is not caused by psychoacoustics? The answer is clearly no – the effect of the filters, is in fact at best very subtle for our ears.
However there is indeed a slight, subtle difference between the filters when especially looking for it doing critical listening – to my ears, this difference is only in the way the note attack in the treble is presented. While the frequency response difference between filter #1 and the rest is too little and happening too high to be relevant or audible, filter #1 and #6 have the “sharpest” treble attack to my ears. The other filters are slightly “softer” than it, with #2, #3 and #4 sounding similar and #5 being even a tad “softer”. #7 sounds a tad “smeared” in the treble attack to my ears.
But again, those are just tiny nuances and very, very subtle at best, and I definitely wouldn’t bet any money on discerning them in a blind test, because I would definitely fail. Just don’t think too much about the filters and leave the setting at filter #1 at best. And by the way, no or only very subtle audible differences between the different filters are completely normal and the way it should be – hearing greater, easily reproducible differences would lead to the conclusion that the filter implementation (that is supposed to be mostly outside of the audible range) is done poorly.


I consider myself as someone who is rather sensitive to hearing hiss and have also got some very sensitive in-ears (for example the Shure SE846 and Ostry KC06A that are among the most hiss-revealing models on the market). So with the right in-ear, I hear hiss to a varying degree with about any digital audio player (in fact out of the players I own, have on hand and have heard, only the Cowon Plenue 2, iBasso DX90, Luxury & Precision L3 and Luxury & Precision L3 Pro are basically hiss-free, however the latter two do not have the most ideal output impedance for multi-driver in-ears and those with a varying impedance response).

Using the AP200 with the super sensitive Ostry KC06A (because my multi-BA in-ears’ sound would be affected by the Hidizs’ high output impedance), I am surprised and very happy to say that the amount of hiss that I am hearing with an empty audio file and in quiet passages of the music is very low and rather close to being not present/inaudible wherefore it is little enough to be rather irrelevant.
No, ultimately the AP200 isn’t 100% hiss-free, unlike the DX90 and Plenue 2 that really have that hiss-free, *cough cough* “black background”. But it hisses way less than the majority of other audio players on the market, and also considerably less than the quite hissy AP60. Good job, Hidizs.

Subjective Perception of Transparency, Precision & Soundstage:

Now to the rather subjective part of my review. My opinion and experience concerning the perceived “character” and “transparency” of source devices and amplifiers is as follows: there can be an existing audible difference between various devices, but it should definitely not be overrated – simply because the basic character of a headphone won’t be completely changed (if the circuit follows a clean design philosophy and the output is load-stable), but sometimes rather slightly “shaped” and is usually very subtle in many cases, and is (in most cases) just slightly present (if even there) and not “huge” or like “totally different classes” or “night and day” (modern and linear measuring audio gear are no effing music instruments, for eff's sake!).
I am not a fan of exaggerations and hyperboles here because as long as the objectifyable parameters of an audio player are neutral and not too shabby (loaded frequency response, distortion, crosstalk, dynamic range, noise, …), the audible difference, if there is any, will be quite small at best if two devices are compared with proper volume matching that cannot be done by ear but only with instruments, since even small differences in loudness can be perceived as a technical advantage by our ear and brain.

A more detailed, German article written by me regarding the “audible difference between comparable audio devices, if there is any, can be found here: […]

So let’s go on with my subjective impressions and observations (for this critical listening, I mainly used my Sennheiser IE 800 and Audeze LCD-X as well as the Ostry KC06A and HiFiMan RE2000):

It is often said that SABRE DACs tend to have some glare and tend to “aggressiveness”. While it ultimately comes down to the entire implementation of the audio-related components, I would also back this up for some devices – to my ears, besides the audible hiss the HiFime 9018d has, it sounds just like my iBasso DX90 to me, which could be characterised as sounding and measuring neutral but somehow having some kind of “aggressiveness” and “speed” when it comes to treble attack. This is even more present to me with the Zorloo ZuperDAC-S that, while measuring neutral and flat as well, gives me the impression of a somewhat “aggressive”, “speedy” and “accelerated” treble attack using in-ears.
Then there is the Chord Electronics Mojo that seems to render cymbals “unaggressively” and appears to “take away an edge”, somewhat just like the iBasso DX80 that surprisingly also keeps this slight character over its line out unlike most other audio players that sound entirely identical to me when having their line out connected to an external headphone amplifier.

To my ears, the AP200 falls rather into the first category and reproduces a slightly “crisper” treble attack that people often seem to associate with SABRE chips.
The signal output is clean thanks to the good hiss performance, and therefore the AP200 also sounds nicely transparent. While I had several sound-related things to criticise about the AP60, there is none of that with the AP200 – it is a clean, transparent sounding digital audio player with a bit of that “SABRE-crispness/glare”, and its only flaw is its high output impedance.
Sometimes audio players seem to have a slightly soft bass with very sensitive in-ears that perhaps might be caused by some hissing in the lower frequencies. This is also nothing I can hear when using sensitive in-ears or planar magnetic headphones together with the AP200 – just a tight and controlled attack in the lows, the way it should be, is what I can hear.

While I usually cannot really hear a reproducible difference in terms of soundstage reproduction among various audio sources when using full-sized headphones, there can be a slight difference to my ears when using sensitive in-ears with a three-dimensional soundstage on various sources (that have an output impedance that is low enough so it doesn’t change the in-ears’ frequency response).
To my ears, just like the iBasso DX90, the AP200 creates a somewhat wider than “average” (e.g. iPhone 4, FiiO X3 first generation, iPod Nano 7G & 6G, iBasso DX50, Cowon Plenue M2, Chord Mojo) soundstage, with a more elliptical than circular presentation, similar to just-mentioned DX90 and HiFime 9018d.

Keep in mind though that these differences mentioned above are actually very small in quantity when comparing two or more audio devices with proper volume-matching.

- - -

So in terms of sound, the AP200 delivers just what I expect from a good audio player (clean, transparent, tight, neutrally measuring, good hiss performance). Thumbs up. Solely the high output impedance is sort of a show-stopper for multi-BA in-ears, which is a real pity – if the AP200 was as poor in terms of sound as the AP60, I wouldn’t mind and say that it’s designed and intended as a digital transport source; however the AP200 is really good when it comes to sound output, and therefore it is a true pity that they didn’t get the output impedance to be considerably lower in order to make it an almost-perfect digital audio player.

Digital Audio Output (external USB DAC):

Unlike some other digital audio players, the AP200 does not have any coaxial or optical outputs. However, it has got a USB-C port and can be connected to an external DAC, which is nice. At the moment however, it doesn’t work well with several DACs, such as my Chord Electronics Mojo (ironically one of their sample photos on their website and crowdfunding page shows it connected to that very DAC).
What’s wrong? You get the music to play, however there are glitches and stuttering. Hidizs promised to fix that, but are already way over the promised date. At the moment, there doesn’t seem any info about when (or even if) the update that fixes that issue will be released. So if you are currently looking for a digital transport DAP to feed your DACs, better look for something else or get an inexpensive smartphone if you don’t mind the size.



While the USB DAC feature supposedly works natively with Linux and Mac computers, drivers need to be manually downloaded and installed from the Hidizs website to make the AP200 work as a USB DAC when connected to Windows computers. The installation is pretty simple though and only needs to be performed once.
Once the drivers are installed, the AP200 can be set to DAC mode using the drop-down notifications menu, and then it even displays the sampling rate and bit depth, which is really nice.



I only briefly tested the Bluetooth feature with the MEElectronics Air-Fi Matrix² headphone and the Mass Fidelity Relay stationary Bluetooth DAC, but what I can say is that the quality is, as expected thanks to the aptX-capable Bluetooth chip of the AP200, good and a bit higher than most already good non-aptX streaming sources, and just as good as any other aptX-capable source.

Apparently the AP200 is also supposed to work as a Bluetooth audio receiver, however this is a feature that I didn’t test.

Bluetooth can of course also be used for various other purposes such as file transfer, adding an external keyboard or a remote.

Gapless Playback:

Once it is enabled in the AP200’s settings, gapless playback does work perfectly with FLAC file. There is no glitch between transitions, no ever so short gap and also no end or beginning of either track is cut off during songs that have been recorded/mastered with a gapless transition in mind.

- - - - - - - - -

Comparison with the iBasso DX90:
Needless to say, the compared devices were properly metrologically volume-matched as close as possible, else the comparisons wouldn’t make any sense due to slight volume differences that could be interpreted as a higher amount of details etc.
Here, I mainly used my Audeze LCD-X, my Sennheiser IE 800 and the HiFiMan RE2000 with digital filter #1 for direct comparisons.

Both are comparably compact, with the AP200 being slightly taller but also slightly narrower than the DX90.
Both are built well, however the AP200 appears a bit more premium due to its CNC-milled metal unibody and slightly more modern appearance.
Screen-wise, the AP200 is definitely ahead and features a far superior resolution. In terms of touchscreen responsiveness though, both perform equally well.

The AP200 has got more features (Android OS with Play Store, WiFi, Bluetooth with aptX, more internal memory (32+ compared to 8 GB), digital USB output) whereas the DX90 has got a line output and coaxial output as well as an easily replaceable battery and a three-stage analogue gain switch while the Hidizs doesn’t.
Both have a dual-mono implementation of the audio path, however no balanced output (that I don’t care much about anyway).
The AP200 has got the more potent CPU wherefore card scanning speed is higher. Its stock player app’s user interface is more modern as well and has also got a search feature that the iBasso doesn’t have, nonetheless both unfortunately lack a track counter on the playback screen.

The DX90 has got the clearly more precise volume control (256 steps with linear 0.5 dB per step attenuation compared to the Hidizs’ purposely limited 100 steps), however listening at quiet levels using super sensitive in-ears is easily possible with both.

Both measure flat and neutral without a connected load or with a simple load, however the DX90 has got the much lower output impedance (only ~ 0.1 Ohms) wherefore it is suitable for all multi-BA in-ears, whereas the Hidizs unfortunately isn’t due to its high output impedance.
Both audio players are really good when it comes to hiss performance with super sensitive in-ears, however the DX90 is even a bit better, being pretty much completely hiss-free.

The AP200 has got an even slightly “crisper” treble attack and slightly higher perceived transparency, however the DX90 sounds a bit “cleaner” in comparison (probably due to even its lower hiss output into extremely sensitive in-ears). Both are perfectly and equally tight when it comes to bass reproduction.
Soundstage width is pretty much similar, with the AP200 having a tad more front projection.
Keep in mind though that all of these sonic differences are very small and rather nuances, objectively regarded and when performing properly volume-matched comparisons.


Hidizs’ AP200 features a nice, modern design, is available with many different design options, has got good build quality, is priced attractively, comes with WiFi, has built-in Bluetooth with aptX, features very good hiss performance with extremely sensitive in-ears, has got a clean, detailed, transparent sound, and works well as a streaming source (however, depending on your environment, there might be occasionally audible WiFi interference noise with enabled WiFi, which is something to consider).

All of these features would make it a nearly perfect standalone digital audio player with streaming capabilities – if there wasn’t its high output impedance that is not ideal for low impedance in-ears and headphones with a non-flat impedance response, such as the vast majority of in-ears with Balanced Armature drivers. Therefore, as a standalone player, the AP200 is better-suited for dynamic driver in-ears and full-sized headphones (as long as they have a flat impedance response or are have an impedance high enough so it isn’t affected by the Hidizs’ output impedance). And the other issue is that the USB DAC Output feature that was promised but didn’t find its way into the AP200 yet is still to be implemented through a firmware update (that was promised but doesn’t seem to be finished yet – bummer).


End words for this review: The AP200 is a surprisingly great digital audio player with WiFi streaming and aptX Bluetooth. And its sound output is nice – clean and transparent – wherefore it has (fortunately) almost nothing in common with the rather sub-par AP60 that is quite a failure as a standalone player and only works well as an inexpensive, purely digital source (however the AP60’s USB DAC Output does work as opposed to the AP200). The only area that needs improvement on the AP200 is its output impedance that is simply just too high for multi-BA in-ears (and I personally wouldn’t mind to see the player using all of the DAC’s available 256 volume steps), as well as the promised USB DAC Out feature (heck, it was a promised launch feature, and the people at Hidizs didn’t even meet their promised target of “end of March” to fix that issue after it was publically known).
1 more star if the USB out feature that was clearly promised was working - it's a promised feature, so Hidizs, please finally get it to work (I personally do not need it, but some people clearly bought the AP200 because of that promised feature, as the thread shows)!


Enjoyed this mate. V detailed, and results of your measurements make for interesting reading.
Pros: Sound quality, easy to navigate
Cons: Build quality, firmware still needs some work
Firstly I would like to thank Hidizs for sending me this sample to review, it has been used for a good fews weeks before reviewing.

*disclaimer: This sample was provided for the purpose of writing a review, no incentive was given to write a favourable review. All opinions expressed are my own subjective findings.

Gear Used: Hidizs AP200 > German Maestro GMP8.35d / Inearz P350 / Custom Art FIBAE 3 and others.


Tech Specs:

Packaging, Build Quality and Accessories:
The AP200 comes in a neat matte black box, with the brand name and model number embossed on the front, on the back is a list of the main technical specifications and also a list of included accessories. The AP200 is held in a foam insert; underneath this you will find the accessories. The box is neat, and not excessive, overall a great unboxing experience.

Build quality overall is good, the buttons click with authority, and the sockets are all nice and tight. The housing is aluminium, and well finished however mine is the blue version with the standard glass back and there is already a crack in mine even though it has been kept in its case. I am not sure if mine is a one off as it was going to a reviewer and was possibly not a full retail unit QC wise, but it is a shame to see it crack so easily, I think Hidizs could use stronger glass on the back panel. The front is fine, and overall it is a well made DAP.


Accessory wise you get extra screen protectors (one is already installed from the factory), a thin plastic case, a USB-C cable and also another shorter USB-C to micro USB cable. You don’t get anything fancy with the AP200, but for the price it comes with the essentials that most players come with so I cannot complain. The case is a bit on the thinner side, but it is good to have a case on the player, the optional Leather case in my opinion would be much better at protecting the player.


Features and UI:
The AP200 does not have balanced output, it does not have digital output apart from USB output, which works for me but is still not 100% working for some people. The AP200 does have 2 modes, Android or pure music mode, in Android mode you have access to the playstore where you can download apps and use streaming services. In pure player mode you only have access to the installed hiby player, but I will note that Bluetooth and WiFi both work in pure player mode.

The WiFi is not very well implemented, the signal drops out a lot and does not have very good range, so this is something to be aware of if you are planning on using it as a streaming device.
The Bluetooth is actually very good however, and it supports AptX, you can tell if it is sending an AptX signal by a small A symbol appearing in the notification bar. I got good range with Bluetooth, and the sound quality is good via AptX.

The settings menu will be familiar to anyone who has used Android, so I won’t go into detail there, the only difference being the Audio settings. You have 7 DAC filters to choose from, these are subtle and it is best to play around with them to see which you prefer. I have it on Minimum phase, fast roll-off but you can pick whichever you prefer. You also get high/low gain options and also a channel balance option.


The screen is sharp for a player of this price, and has good colours; unfortunately the calibration is a little off, and I believe further firmware updates can help here. When the AP200 originally came out it was incredibly slow to navigate, but with the latest firmware it is a lot more responsive and I have no real navigation problems.

The AP200 uses a custom version of the Hiby player app, which is really easy to use and it also looks great, you have the usual track info on the now playing screen, you also have the option to add the track playing to a playlist.
You also have an EQ, Gapless, pause when headphone is unplugged, DSD mode and some other little options in the Hiby app.
Button wise you have the power button on the top, on the side you have a play/pause button, and the volume buttons. The volume buttons also skip and rewind tracks if you double tap them quickly. In the previous firmware it was hard to turn the volume up a few steps without changing tracks, but now the delay between two taps to change tracks is a lot shorter so it’s easier to adjust the volume multiple steps without accidentally skipping tracks.

As with any player there is a learning curve, but the AP200 is an easy to use android base DAP that doesn’t take long to get used to. Volume steps are small so you can easily get good volumes with sensitive IEM’s, along with it doing a respectable job with full-size headphones.



Despite a few bugs in the firmware, the AP200 sounds truly excellent, it has such an engaging and detailed sound that you sometimes forget about some of its quirks. The AP200 may not have a balanced output, but with the single ended output sounding this good it really doesn't matter.

The AP200 is not the smoothest, most refined sounding DAP around, but what it offers is a fun and enjoyable listen with a sound that is packed full of detail. The bass is tight, but powerful and punchy; there is perhaps a slight bit of added sub-bass body. The midrange is open and detailed, and the highs have a little added energy to bring out a little extra sparkle.

The slight boost in the treble is expertly implemented, as it does not make the AP200 come across as thin or bright at all. The other thing is that even though it sounds like there is a slight boost down low and up top, the midrange is not missing a single thing, it remains wonderfully open, airy and detailed.

The AP200 has a very powerful internal amp, with excellent transient response, even the most complex of tracks never sound blurred or muddy. The soundstage is effortless and wide, the separation is also precise.

As I said, the AP200 is not the most reference sounding DAP I have heard, but it is one of the more engaging and enjoyable DAP's I have used.


Audio Opus #1s:

First off the Opus #1s is a pure DAP, without the bells and whistles of the AP200 (no wifi, playstore, bluetooth or open android). The Opus #1s runs a heavily modified version of Android, and it just works and is really easy to navigate which I appreciate. The Opus #1s also does not have DAC filters, but it does have high and low gain, it also has a 2.5mm balanced output (and optical output)

From a usability point of view, the Opus #1s is more refined, less buggy and easier to use, but the AP200 has many more features which can be useful.

Sound wise:
The Opus #1s is fuller bodied with a little less sparkle up top, the AP200 jumps out with a more engaging and sparkly sound but digging deeper you will find that the layering and sounstaging are superior on the Opus #1s

The Opus #1s has very tight but full bass; there is a hint of bloat when using the AP200. The soundstage is wider, but the AP200 has slightly more air around instruments. The separation is more defined on the AP200.

Overall they are both excellent players, the Opus #1s sounds a little darker, but has better layering and soundstaging. The AP200 has slightly better detail retrieval, separation and is a bit more engaging.


Conclusion: If we are basing this off of sound quality alone, the AP200 is an excellent sounding DAP. Unfortunately the firmware is still not quite perfect, and there are some quirks still to be ironed out. Saying that the latest firmware really did bring this DAP a big step closer to being an excellent daily driver.

The wifi range is terrible, bluetooth works but again the range isn't the best, the touchscreen calibration is still slightly off and the back of mine has a crack.

BUT the sound is excellent; it is dynamic, engaging and highly detailed for the price.

Sound Perfection Rating: 6.5/10 (if it didn't sound this good, it would not be getting this rating)
Pros: Good battery life
Solidly built
Cons: Buggy
Poorly implemented
Poor to average sound quality
Quick Read Conclusion

An unbelievably versatile piece of kit that promises far more than it can competently and consistently deliver. The numerous fundamental glitches and so-so sound quality make it impossible to recommend at its price point. If Hidizs can get the firmware right, this moves from unusable to average, but for now I have to warn people to stay clear as I feel my money has been wasted.

Introductions and General Bumf

I was a subscriber to the IndieGoGo campaign for the Hidizs AP200, and paid my US$269 for a Hidizs AP200 ("AP200") with a leather case included. For clarity, I am in no way associated with Hidizs and have received no inducement to write my review.

Further, Hidizs have a very thorough description of internals on their website so I point you (for a full set of specs) to:


Test Kit: I have tested the AP200 with Shure SE215, SE425, Sennheiser HD600, Ultimate Ears UE900s and KEF M500 headphones/IEMs. I have also tested it as a USB DAC with a Samsung Note 8 and Galaxy S8 (using both Hiby music and UBS audio player pro), Dell E7270 running Windows 7 and an 11" Macbook Air (2012 vintage). I have also used it as a USB transport for the Schiit Modi 2 Uber and iFi Audio nano iDSD Black Label ("Nano BL") and finally I ran it through a Schiit Vali 2 to compare against the Nano BL.

with vali.jpg

Preparation: I have given the AP200 a shade over 50 hours of burn-in (unsure if I believe in burn in, but figured this should help for people who do) and I did not start any critical listening without giving it at least an hour to warm up (I think warm up of DACs does help, and have read a couple of papers on this, but given this is a "mobile" device I don’t think real world use will involve having had this thing plugged in for 24 hours before listening).

Me as a listener: I am not a pro by any stretch of the imagination. I have always enjoyed my music, and my tastes are pretty broad. I go to live music ranging from rock and pop concerts to orchestra and opera. I would not describe myself as having a trained ear, but I am attentive and my ears are in pretty good nick for a 34 year old (my hearing cuts off around 17.5 kHz per my frequency generator).

My tastes: neutral to warm, but I do like good punchy bass and I love to hear decent instrument separation.

Test tracks: I've tried to keep it broad and I have cited my music sources below, so (where possible) people can download the tracks themselves.

1) Wiz Kalifah – On My Level (320k MP3, Google Store)

2) Norah Jones – Turn Me On (24/192 FLAC, Qobuz)

3) John Williams – Throne Room from Star Wars performed by Prague Philharmonic Orchestra (16/44.1 FLAC, Qobuz)

4) The Verve – The Drugs Don’t Work (16/44.1 self ripped FLAC)

5) Ed Sheeran – Castle on the Hill (320k MP3, Google Store)

6) Grieg – In the Hall of the Mountain King (from the Peer Gynt Suite) performed by the Zech National Symphony Orchestra (24/48, Musopen Kickstarter Project)

7) Otis Redding – Dock of the Bay (24/192, HD Tracks)

8) 30 Seconds to Mars – Stronger (Radio 1 Live Lounge Cover) (16/44.1, self-ripped FLAC)

9) Pearl Jam – Yellow Ledbetter (320k MP3, Google Store)

10) Rage Against the Machine – Wake Up (292k m4a, iTunes)

So, on to the main event. [/General Bumf]


I have to say that this was a premium experience, and leave the photos below for you to make up your own minds. The solid card box, well-engineered packaging and classily understated product packaging all contribute to making this a special experience. In the box are the AP200 (with anti-scratch film fitted in factory front and rear), a usb a-c cable, usbmicro-c cable, clear plastic shell case, serial number card and quality control card and a spare set of anti-scratch films. I particularly liked the little bit of ribbon underneath the device which made the "pop" out a tactile experience.

First thoughts on unboxing are that this is a quality piece of kit. The CNC machined body which Hidizs have banged on about is chunky and has a good weight in the hand. I also like the leather case which it came with, and fits snugly inside – it has a lovely recessed Hidizs logo stamped in, and adds to the overall quality feel of the product.

Finally, there is a note inside the lid, telling you to update the firmware… more on that later.

unboxing 1.jpg unboxing 2.jpg unboxing 3.jpg unboxing 4.jpg unboxing 5.jpg unboxing 6.jpg unboxing 7.jpg


By my measurements, the unit is 106x60x16mm, add about another 2-3mm each way with the leather case on. It has a decent weight but is definitely pocket friendly. I like the little notch which is recessed for the 3.5mm standard headphone socket, and the recesses at the bottom for the USB (type c) port and micro sd card slot. I find the usb port a little lose with cables other than the one it came with, which is surprising as my other cables (OTG, and some decent quality a-c cables) fit my Samsung phones without issue.

There is a power button on the top and volume control (which doubles as track skipping) and play/pause buttons on the left hands side (more about these in the niggles section below).

Battery life is solid – I'm getting about 8-9 hours with the volume at 25 listening to flacs on iems on high gain.

The screen is high resolution (960x640) and the quality is reasonable, no dead pixels on my unit, although there is light bleed around the edges. On a phone this would not be acceptable, but on this unit I think fine given it is for listening to more than looking at. It is a little dim in bright sunlight, but just about legible and (again) amply sufficient for a DAP.

The unit is a real "one stop shop" running a slightly customised version of android, and capable of downloading additional apps via the Google Play Store (WiFi File Transfer Pro works fine) as well as being able to:

1) bluetooth out, works fine;

2) USB data out to a DAC, sort of works, see niggles below;

with nanobl.jpg

3) operate as a USB DAC, subject to the proviso in niggles below re/bit rates, works fine with Windows, Android and MacOs but you need to download the driver to get the full benefit of its output potential.

In theory, you could download all sorts of additional apps to use on this, but the small screen space coupled with the fact I always have a Note 8 on me, means I haven’t really done much else with it (it is capable of browsing the web, jittery YouTube playback but I haven’t tested this extensively as it is not what I bought the device for).

There is also sufficient power for my HD600s. On a volume scale of 0-100, 70-80 (high gain) is a nice listening volume and 100 simply loud but not completely ear splitting. I suspect therefore that for most cans this will be sufficiently powerful but doubt the AP200 has the required oomph to push something very hard to drive,

The Sound

I have decided to split my review into the standard format of highs, mids, lows and also soundstage and separation, as it is something I enjoy hearing.


I find the highs on this unit a tale of two halves. Played through my M500s, SE425s and SE215s they are prominent and a little more forward than, say, through my Schiit Stack (Modi 2 Uber and Vali 2) or Nano BL, but still pleasant. This is true across the board for certain tracks, where there is an obvious and entertaining "tingle" on the high end.

On the HD600 and on the UE900s however, there is a noticeable harshness, with a metallic tinge which (emphasized on certain tracks like Ed Sheeran's castle on the hill and anything guitar heavy, especially steel strung acoustic) I find unpleasant. It's an experience I would compare to sitting on the train sitting next to someone whose headphones are bleeding highs; if you concentrate, you can hear the rest of the track, but the ear is a little overwhelmed by the tinny percussion.

Mids and Lows

There is not a huge amount for me to say here. Competent, clear, detailed but unremarkable is about the best I can do. There is a little enhancement at the lower end which is noticeable in some of the bassier tracks noted above (Wiz Kalifah for example). I think the sound signature is broadly U shaped then, with an emphasis on the bass and treble, and the mids present but nothing specifically identifiable to my ear.

Soundstage and Separation

Soundstage is definitely wider than the outputs on my S8 and Note 8, with (for example) the guitars on the Verve's Drugs Don’t Work placing themselves noticeably to the left and right of centre. I would put it on a par with my Schiit Stack, but there is not the breadth of stage (nor the clarity of instrument separation) that I get with the Nano BL. In some more busy or layered tunes (Ed Sheeran and the Throne Room tracks noted above being good examples) the sound gets a little muddled or blurred, with specific instruments in the orchestra or layers of Sheeran's vocals barely distinguishable.

Sound Conclusions

Outside of this community, most people these days listen to average quality MP3 music on their phones. The AP200 is undeniably a step up from that experience across the board – the sound more refined and clearer, the "veil" lifted, especially with higher quality files. The problem for me though, is that I have heard, at similar (and lower) prices a hell of a lot better for the same money. In terms of portable solutions, my old dragonfly v1.2 and my Nano BL both leave the AP200 in their dust. In short, I was underwhelmed and disappointed, especially given the hype… 2 gold shielded DACs must make it sound amazing, right? Erm… nope.

Niggles and Solutions

My biggest issue with the AP200 though, is it feels rushed to market and exceptionally poorly implemented – indeed, spend 5 minutes in the forums and you will find a snag list as long as your arm. Before I give my list, I confirm I am running the most current firmware (as at 2 January 2018) and that all of these issues remain on that version of firmware. Some of these issues are fundamental to the experience, and so I tried to organise in running order of serious to incidental.

1. problems in sound during playback – on top of the harsh treble I have already described, the AP200 randomly pops and clicks when playing (it's the sound you sometimes hear from a DAC when it is changing from PCM to DSD and/or bit rates/frequencies) but it happens mid playback and substantially detracts from the enjoyment of music;

2. stops playing randomly – mid track, the AP200 (reasonably regularly) clicks, pops then stops playing completely. Sometimes these resolve and playback starts again, sometimes you have to fish it out of your pocket, and press play/reboot to bring it back to life;

3. volume/track selection – this is ridiculous and horrendously implemented. By making the next/previous track a double click on the volume button, I often randomly turn up/down when I am trying to skip and skip when I am trying to turn up/down;

4. USB out is buggy – I can only get the AP200 to play nicely as data transport to my Modi 2 Uber/Nano BL intermittently. I don’t know why it doesn’t always work/how to resolve this;

5. screen presses inexact – the AP200 regularly misses button presses on the screen meaning you have to jab a few times around the relevant button, at which point it registers multiple inputs (and doesn’t do what you wanted it to);

6. screen use is difficult - small text on a small screen, along with a lot of options at the screen extremities lead to a lot of frustrating missed inputs, exacerbated with the leather case on;

7. slow response to button presses – especially using next/previous track or pause during playback on the screen, you can have 3-5 second waits before the AP200 does what you asked it to;

8. firmware updates – despite the claims that you could, I could not get the AP200 to update firmware from an SD card (landing on an android green screen with text input). It did work fine from the internal storage however but I did think I'd bricked the thing;

9. output rates not shown properly – when operating as a DAC and in normal playback, the output bit depth does not match the source (when native, it says everything is 32 bit, when a USB DAC, 24 bit);

10. SD card write speeds are slow despite onscreen claims; and


11. volume controls backwards – the onscreen volume controls are the wrong way around, with the plus on the left… why oh why oh why?



As currently implemented, I cannot recommend this device to anyone. The so-so sound quality means I would probably use it alongside the Nano BL as a playback device if it could play nicely. However, with the numerous fundamental bugs (most annoyingly the intermittent but frequent random stopping during playback) the average sound quality means this little box will be consigned to a drawer for the foreseeable future. I think my $269 would have been better spent elsewhere and this is a clear lesson to me that a "too good to be true" stats list for the price is just that, too good to be true.

Doing some quick calculations - nope, even though the HD 600 doesn't have a flat impedance response either (it's a common thing for open-back dynamic driver headphones and has to do with their resonance frequency), the Hidizs' output impedance is still low enough for it so that the deviation would be clearly below 0.1 dB.
[Continuing here because the editor doesn't allow more characters] I really don't have an explanation for where this impression with the HD 600 that you have compared to the Sennheiser playing from different gear comes from (apart from the HD 600's mild lower treble lift itself of course).
Thanks - understood. I think I tested with the ue900s before the hd600s. It might well have been my own confirmation bias.