Shanling M6 Ultra

Shanling M6 Ultra - Put your foot to the floor with this powerful but compact DAP... $919



Introduction & Caveats

I don't often review DAPs, the previous was actually the excellent Lotoo Paw 6000 last summer, and before that the @Shanling M9. I adore DAPs, and could easily own numerous if money weren't a consideration - this is rooted in my love for consumer electronics, dating back all the way to 1987 when I bought my first Walkman in Singapore when I was about 11 years old. I was visiting my uncle at the time with my Mum and brother, and during the stay I also drooled over his Denon separates and Kef speakers - that was the time I really remember falling in love with consumer electronics, music dates back to my most distant memories as a toddler, most notably Supertramp, Abba and Planxty (a traditional Irish band). I eventually went on to work in the industry, first of all in my teens in an electronic store and ultimately working with brands and distributors - sadly no longer the case, as I changed to another industry about ten years ago, but the passion lives on in this hobby!

I am not a professional reviewer, I enjoy sharing my explorations with the community and hope that they prove useful for even a select few people! The goal of this short review is to give a sense of the features of the M6 Ultra (M6U), and to assist those who might be considering buying one.

I own a few DAPs at present aside from the M6U: Cayin N7, LPGT Ti, LP6K, iBasso DX320X, Sony WM1A, Sony ZX300, Shanling M0 Pro, and Aune M1p (maybe I own too many). My collection prior to that, many of which still in a box include various players dating back to the early 00s, the dawn of the digital age of audio devices, where they were once called 'MP3 players', before simply 'iPods', and now a bit of a u-turn to a more generic 'digital audio player', or DAP for short - at least for those of us in this hobby, I suspect 99% of the world population has no idea they exist, and would likely think we are mad...

Before we get stuck in: I received a small discount in exchange for sharing my impressions, thanks as always to @MusicTeck for their amazing service for the audio community. The M6U is available from MusicTeck HERE



About Shanling (tldr; they've been around a while, and clearly know how to make great audio products)

Founded in 1988, Shanling began to develop audio products and launched their first Hi-Fi stereo amplifier in the same year.

Shanling has launched new products every year since then and has obtained a series of patented technology qualifications, such as SONY LDAC, Bluetooth BQB, Japanese Audio Association Hi-Res, Microsoft's HDCD, Dolby Laboratories' Dolby Digital, DTS and DVD, SACD, CD patent licenses and many more.

For over 30 years, Shanling’s employees kept integrity, innovation, team spirit and hard work in mind. There is no doubt that our employees are our treasure and that without them, we would never get to the Shanling of today. We believe customer’s satisfaction and quality of products are the highest priorities, the realization of user’s dream and sharing profit with our partners are our development power.

Today, main offices of Shanling are located in Shenzhen and factory is in Dongguang. Shanling is a high-tech company combining R&D, production, processing and sales of products, including Hi-Res portable music players, portable amplifiers, Hi-Fi headphones, SACD/CD players, Hi-Fi amplifiers, power conditioners and many other Hi-Fi products. We have established close relationship with many international top hi-end manufacturers and enjoy a good reputation in the industry.

Click to expand...

Specifications

• Dimensions – 127 x 77 x 18 mm
• Weight – 263g
• Display – 5-Inch 1920 * 1080
• Operating System – Open Android 10
• CPU – Qualcomm Snapdragon 665
• Memory – Ram 4GB, ROM 64GB + single Micro SD card slot
• Hi-Res support – 32/768 & DSD512 & MQA 16X
• Bluetooth – Bluetooth 5.0, Transmitter: LDAC, aptX HD, aptX, SBC // Receiver: LDAC, SBC
• Wi-Fi – 2.4G/5G, supporting DLNA, Airplay
• DAC – 4x AKM AK4493SEQ
• Analog Circuit – OPA1612 + OPA2211 + LTA8092 + BUF634A
• Output Power – Single-ended 240 mW@32Ohm // 720mW@32Ohm Balanced
• Output – 3.5mm single ended and 4.4mm balanced
• Output impedance - Less than 1 Ohm on both outputs
• Battery – 5650 mAh, supporting 18W QC3.0
• Battery life – Up to 13.5 hours in single ended and 9 hours in balanced

Unboxing

As noted in most of my reviews, I'm a self-confessed nerd/unboxing freak - it's quite a peak moment in the dopamine cycle of hits when making a purchase, for those of you fellow-sufferers, you will likely know what I mean... that moment just after the ring/knock on the door, and you've opened the outer packaging, and the beautiful shiny box of your new toy is awaiting to greet you. I'll not bore you with the moments that come before and after, but we all know that frantic refreshing of the tracking status - and indeed in some cases imaginary or 'phantom' vans pulling up outside your house... until the real one actually arrives. Or maybe we don't all suffer with this predicament, but I know a few of you who do anyway.

Ok sorry, unboxing... getting a bit carried away there.

Aforementioned shiny box first (Shiny Happy People...)



The lid opens to reveal the wonders within...



The M6U and a separate box of accessories, albeit not very much - and indeed as noted, no case which is a bit frustrating at this price. Side but relevant note, I bought a case from the official Shanling store on AliExpress for about $45.



All of the contents - basically all you need with the exception of a case. On the plus side (which also has a small negative), it does arrive with a screen protector already attached - I have a serious problem with putting these on, so always pleased when already done. Plus you get a spare, and of course a cable...



The Device...

I will start by saying the pictures don't really do full justice for the M6U - it is in my opinion a beautiful looking DAP, that has a real premium design and overall finish. It strikes me as something the likes of Panasonic or Aiwa from the good old days might have made if they remained in this industry, or indeed remained in business in the case of Aiwa (some of you might be too young to remember this brand, but they were certainly big in audio back in the 90s).

I chose the black finish, but it is also available in green - they both look great, but being from Ireland, I didn't want a green DAP - we have enough green around us. Plus I really liked the blend of a black DAP and tan case.

The M6U has a good weight to it, and a nice ergonomic grip - as soon as you pick it up, you feel like you've a premium device in your hand.



Left-side profile: buttons to play, pause, and skip forward and back - easy access, and simple to use.



Right side profile: volume wheel. This feels sturdy and has a nice tactile/click response when adjusting. I found the wheel on the M9 felt a bit loose and often wondered if it might eventually pop off, unlikely but it certainly crossed my mind - not so much that it kept me awake at night.



The earphone sockets are on the top of the device, with 4.4mm balanced to the left, and 3.5mm single ended to the right. I much prefer this to the modular system on the M9, which frankly speaking I found an utter pain the ass after a while.





The rear of the device is eh, the rear of the device I guess - not much to say here, other than it follows everything else in that it has a slick finish, with a nice Shanling logo embedded at the top.



Finally, the bottom of M6U houses the USB charger input and microSD card slot.



For a bit of a size comparison, I've laid out the (from right to left) the P6K, M6U, and DX320X. The M6U is pocketable, but not ultra-pocketable - it's relatively compact, and there is reasonable weight (263g) so you feel it if in say a light jacket pocket. I think it's perfectly ok to take out and about, but a lot of that depends on your clothing and climate - probably not overly practical if say just shorts and t-shirts! I've often had it out and about in an inside jacket pocket and it has been fine, hardly noticed it there.



Functionality

I must say, the M6U is a dream to use - it's super quick, and with the nice ergonomic design you can easily hold and navigate in one hand. The Snapdragon 665 CPU and Android 10 really do give an incredibly fast user navigation experience, with pretty much no lag as you scroll through albums and move about the device in general. To best get this across, I've uploaded a short video - I'm no movie director, but this should get across more than words can do in terms of how responsive the device is.



How does it sound?

I've paired the M6U with numerous IEMs over the last few weeks, and it has travelled with me to the office on a regular basis, plus flew across the Atlantic ocean and over to the far side of the US on a trip to Seattle. So I've got to know and love this device pretty well. It has more than enough power to drive any IEM, which of course goes without saying - but I've had the pleasure also of hooking up some headphones and found the M6U well able to drive them... this being the Denon D9200, JVC SW01, and the Sennheiser HD660S2.

As I type, I'm listening to the Nostalgia Audio 'Camelot' - my favourite IEM at the moment, and the subject of my next review in a couple of weeks. The Camelot has quite a balanced and detailed signature, which provides quite a lot of detail but without being clinical. That said, it definitely benefits from a slightly warmer source that leans a bit more relaxed. Synergy here is fantastic, the lows are given a nice boost and no shortage of space on stage to reveal the details, still managed within the safety of that bit of smoothness or warmth. Mids are well rendered with plenty of space and detail, and ample sparkle up top - all features anyway of this set, but synergy definitely key.

I tried Camelot recently with the iBasso DX320X and found in some cases it leaned a bit too harsh or aggressive - this IEM is definitely better in my experience with a smoother or at least somewhat neutral source. My favourite pairing at the moment is the Cayin N7, but M6U is a close second.




The Custom Art Fibae 5 pairs wonderfully with the M6U - as noted in my recent review of the Fibae 5, this pair could easily be a walk-away combo for in the region of $2k if you felt inclined to grab two wonderful items of audiophile delight, and not climb much further into the realms of diminishing returns - for this money anyone but the most die-hard audiophiles should more than enjoy absolutely any genre of music, in absolutely any listening scenario for many years to come. Again as noted in my Fibae 5 review, if I had to walk away from this hobby with $2k worth of equipment (hopefully this doesn't happen!), I would choose this combo.



Conclusion

Overall, I would describe M6U as a competent mid-tier DAP that absolutely offers more than the price might suggest. The sound is smooth but detailed, and has ample power to drive certainly any IEM, and all but the most demanding headphones. You have detail, you have nice depth and power in the bass, you have smooth mids, and great extension up top - all wrapped up in what I would describe as a 'tepid' signature: i.e. a slight warmth, but not too much so - it's enough to prevent a signature from being cold or clinical, but still allowing plenty of detail and emphasising the qualities of IEMs at any end of the price spectrum. It's fast, beautifully built, and sounds absolutely wonderful - how can I not award it a full 5 stars? I was aware of the wonderul praise this DAP had received before I took the plunge myself, and was delighted to find that my money was well spent. Clearly, the M6U comes with my highest recommendation.

Overview:
Do you ever wonder if part of your chain is affecting your music quality? Maybe it’s your music service, or your cable, or headphones, or maybe it’s your DAC/AMP/DAP. I had the same question, so I picked up a new DAP to figure out what I was missing. Therefore, up for review today is the bang-for-the-buck DAP king – the Shanling M6 Ultra (M6U)! Musicteck (shop.musicteck.com) was nice enough to give me a small discount on my Like New Green M6U in exchange for this review (I guess they don’t make the Emerald Green anymore.) The M6U is the return to form for Shanling after the AKM fire forced them to move to ESS DACs in 2020. Everyone states that this DAP is a return to the Shanling house sound, but since I never heard the older Shanling DAPs, that doesn’t really mean a whole lot to me. What I CAN do is compare the M6U ( Here) to my smaller Shanling M3 Ultra (M3U) (Here) with the ESS chip and give you an idea of what you get for an extra $500.

Side Note: This is the first non-headphone I’ve reviewed with the new review format, so while a 79/100 may look low, it’s better than the M3U would get if I re-reviewed it today.



Build Quality / Design / Specs (18/20):

For starters, you get 4x AK4493SEQ DACs, a design that goes back to Shanling’s CD players. On the M3U, you get 2x ESS ES9219C DACs instead – less power hungry and technically lower end. You get an 8-core Qualcomm Snapdragon 665 CPU with Android 10 – a really good option with the native Google Play store. You get the same thing form the M3U, which is really impressive for under $500 – though the new Hiby R6 Gen 3 now has Android 12 (https://shop.musicteck.com/products/hiby-r6-gen-iii-portable-digital-audio-player), so that may be a good alternative to the M3U. The M6U also outputs 720mW @ 32 Ohms (not 320 like their site says) with the balanced 4.4mm jack – THAT is really impressive for a small-ish portable player. That much power can run full-size headphones with ease, almost all of them in fact. The M3U tops out at 260mW @ 32 Ohms. The M6U supports 32 bit/ 768 kHz & DSD512, while the M3U is limited to 32 bit / 384 kHz & DSD256.

The M6U has 2x high-voltage Linearin LTA8092 op ams with a BUF634A which allows for a warmer relaxed sound and independent fully balanced output. There’s also a bunch of other Numbers and Letters involved with the M6U if you’d like me to list them, but I don’t feel like it because most people won’t have a clue what I’m talking about. If you want to know more, look at the images on the Musicteck website. The M6U has a 5650mAH battery, which is bigger than most smartphones, but it only offers 9 hours of balanced play or 13.5 hours of single-ended. It also has fast wi-Fi and Bluetooth 5 if you want to stream it to other things like the excellent FoKal Mystique (also available on Musicteck Here.)

The build quality is fantastic and I’m glad I got one of the last Emerald Green ones. The M6U comes with screen protectors installed on the front and back of the glass and the body is made from aluminum. There are also plastic protectors on the top and bottom to prevent scratches when plugging in cables. The buttons are high quality and I love that the on/off button is also the scroll wheel for volume. The back/stop/play/forward buttons are large enough, aluminum, and have a satisfying click. No annoying touch controls for volume here like on the Fiio M11. It’s the same on the M3U though and I prefer the round skip track buttons on the M3U for telling which button is which without having to look. Overall, the M6U is fantastically built with some top-tier specs.



Accessories (5/20):
It comes with ALL of the accessories. Like…umm…ok, it doesn’t come with any actually. Unless you count the pre-installed screen protectors – then it comes with those. Oh! And a USB-C cable – YESSS. But wait, no 18W charger included, so you can use any of the 236 USB-C cables you already have – guess that’ll sit in the box. Then…a case right? Most higher end DAPs come with a case, even the $3,600 A&K SP3000, and the much cheaper Fiio M11. No? What? No case? I get the lack of case on the M3U, it’s a cheaper, low-end DAP, but why not on your mid-tier DAP that weighs a half a pound? Oh, wait, there is a case…on Amazon…for $40… OK, not cool Shanling – at least it’s not $200 like some companies. Yes, I bought the damn case (Here if you want one.) Considering they’re one of the most miserly companies around, this doesn’t really surprise me, but dang – you drop this thing without the case and you’re F’d. So, add the case to your total price when shopping for this. There’s not even a 3.5mm to 6.35mm adapter (my Topping DX5 came with one of those.) So, yeah, not a well appointed DAP for accessories.

I will say that it does come with a nice green leather box. So that after you open it, you can feel guilt about throwing away such a nice box that serves no purpose once you’ve taken the DAP out. Maybe you like keeping the DAP in the box on your desk an opening it to show it off to people like some sort of ancient Mayan treasure? You do you boo. Seems like they could have spent some of the leather box money on an included case instead.



Software / Setup / Ease of Use (20/20):

Well then, surely they put all of their money into something if not accessories right? Yes, right. The android 10 software is top notch. Make sure you go into the bottom right corner under purple Tech Support App and download any updates – this goes faster on the M6U than the M3U. After that, download music or install your streaming app of choice and you’re set. Tidal was super easy to install and setup – MQA happens automatically as long as your settings have quality set to Master or HD. I mean that’s it, I can’t ask for anything better here – it just works great.

A quick note on the screen: the screen looks really good, not that it really matters since I don’t use this for anything other than music and the screen is off most of the time to save battery life. It’s also slightly more responsive than the M3U and easier to hit what you’re trying to tap. Yeah, literally zero complaints in this section.



Performance / Sound (16/20):

Speaking of sections I have zero complaints in, the performance and sound quality is another section I cannot complain about. While the sound quality is not insanely higher than the M3U, it does add a special “something” to higher-end IEMs. In fact, I wasn’t very impressed with the Kublai Khan until I got the M6U and then I had to completely rewrite the review for those. The same goes for the Multiverse Mentor – it sounds fantastic on the M6U and on the M3U, it just sounds fine. More on that in the comparisons section. I’ll be honest, I don’t have enough DAPs laying around to really compare the sound of this to anything other than the M3U – someone send me an iBasso DX320 or A&K SP3000 ok?

Here’s the reason this section loses some points. The battery and the gain. The M6U has a ton more power than the M3U, and I mean a ton – it’s able to power just about any full-size headphone. So why do I need to turn it to a higher volume on the M6U than the M3U to power the same IEMs on low gain? No clue. OK, it has a bigger battery, and more power, which apparently I’m not using since I have to turn it up louder, so how do I end up with almost half the battery life? I legitimately don’t understand that, and I understand electronics better than most people. I guess the output is just using more power no matter what the volume, or the efficiency is just much worse since there’s twice as many DACs? Anyway, the battery life sucks, even on low gain. I use about 10-12% and hour on low gain at volume 35/100 (8-9 hours of battery life.) That’s probably my biggest complaint about the M6U, though other high-end DAPs are pretty similar, so it’s not that it’s terrible in this class, just that it’s nowhere as good as its little brother on battery life. The M6U does have quick charge though, which works…OK, and fills that battery back up decently. The M6U also get hot easily, just like the M3U – the leather case helps, but apparently the SP3000 doesn’t do that. My M3U once got so hot in my pocket that it shutdown and refused to turn back on until it cooled off – it also has more weird software glitches for some reason.



Comparisons / Price (20/20):

On Takida’s “You learn”, the Multiverse Mentor sounds open, with a large 3D soundstage and each instrument enveloping you in a 360 degree field. The bass is warm and everything can be heard clearly. The M3U just sounds flatter - more 2d than the M6U. The vocals are significantly more forward (somehow) but there isn’t as much bass or warmth – and I prefer the vocals still on the M6U. The soundstage is definitely flatter and less engaging. The M3U removes the emotion that the M6U portrays on what is literally one of the most emotional IEMs I own. There is also more sharpness on the M3U – it’s just not as good, which is pretty surprising listening to these back to back. It makes me wonder how many IEMs I’ve rated poorly because of the M3U rather than the IEM itself. That said, the M3U is half the price and still a fantastic budget DAP. If you’re not listening to high-end IEMs, the M3U may be all the DAP you need.

OK, the price – the M6U is not a cheap DAP, but it’s also not an expensive DAP. Sort of like the Thieaudio Monarch is expensive, but not an expensive IEM. $919 for top-tier sound is not a bad price at all. Is it worth spending an extra $2,500 to get the A&K SP3000? Not to me, but if someone wants to let me borrow one, maybe after hearing it I will want one – who knows? Regardless, there’s really not much else in this price range, and certainly not with this performance. The M6U hits above its price range, likely at least to the $1,600 iBasso DDX320.



Conclusion:

We always talk about that extra 10% you get from going more expensive, well, the M6U is the middle ground between cost and performance. I can confirm that it sounds better than a cheaper DAP with similar DNA. The battery and lack of accessories really hold it back, but the ease of use, sound quality, and build quality are fantastic. It really brings higher-end IEMs alive and moves that doubt in the back of your mind that your source is holding you back. Unless your mind then tells you to get the SP3k because if the M6U is better, then the SP3K must sound EVEN better haha. At that point, welcome to The Hobby.

Wolfhawk’s Rating: 79/100

What’s the point of digital audio players (DAP) in this day and age?

That question has haunted me since I realised that the “bricks” that many at my local hi-fi store use are oversized MP3 players (no, sorry, DAPs). Why would anyone want a device that cannot stream online music or has an obsolete Android version? Sound quality? What’s the point, given that perfectly measured DAC/amp dongles exist?

Despite my scepticism, I couldn’t help but yearn for one of those bricks. Recently, I acquired a portable DAC/amp unit and was sure that the madness over “bricks” was over.

It was, in fact, not over.

Let’s talk about Shanling M6 Ultra (M6U) and what life with a DAP looks like.

Preambles​

• I use the term “source” to denote a DAC + Amp combo.
• Sources do not make sounds. Therefore, when I say sources “sound” a certain way, I talk about the change they make to my IEMs and earphones.
• I want my music to be crisp, clear, well-separated and form a 3D soundstage around my head. Sources that intensify those characteristics of my IEMs are considered “better”.
• This review is based on my subjective experience. Ratings are given based on A/B tests with benchmark sources and IEMs.
• Making loud noises does not mean that a pair of IEMs or earphones are driven to their full potential.
• Despite my textual descriptions, improvements from sources are minor and nuanced. If you are beginning your head-fi journey, getting different IEMs or earphones would yield more benefits. If you know your gears very well, improvements from sources can be delightful.
• The M6U was purchased at a discount directly from Shanling for this review (Thank you!). The unit retails for USD $920 on Shanling’s Amazon store (non-affiliated link).

Specs​

• DAC Chips: AK4493SEQ x 4
• Output ports: 3.5mm (Single-ended) and 4.4mm (balanced)
• Single-ended output power: 240mW@32ohm per channel
• Balanced output power: 720mW@32ohm per channel
• Battery: 5650mAh (13.5 hours 3.5mm, 9 hours 4.4mm, 58.5 hours Bluetooth)
• Quick charge: Qualcomm QC3.0 18W
• Bluetooth 5.0 (Receive: LDAC & SBC, Transmitting: LDAC, aptX HD, aptX, SBC)
• Android 10 with built-in Android Global Lossless Output.
• 4GB ram, 64GB internal storage
• MQA support: 16x

Non-sound Aspects​

First thing first, what is Shanling M6 Ultra?

It is a DAP (or an oversized MP3 player, if you will). M6U sits right in the middle of Shanling’s DAP line. It is one step above the M3 Ultra, side-by-side with the older M7, and one step below the flagship M8 and M9.

The best way to think about M6U is an Android phone without the ability to receive and make phone calls. Instead, it is equipped with a high-end DAC (digital analogue converter) and amplifiers. This little brick can serve many different purposes when it comes to audio.

But we are getting ahead of ourselves. Let’s start from the top with the unboxing experience.



After weeks of (impatient) waiting, I couldn’t wait to rip the shipping box apart when it arrived at my door. Since I’m more used to the futuristic, sci-fi aesthetic of Fiio and Hidizs, I was pleasantly surprised by the elegant packaging of Shanling with the faux leather box and the green tone. My first reaction was to bring the whole package to my wife, and she also had to admit that the presentation was worthy of a luxurious item.



The content of the box is less glamorous. You have the DAP, a nice USB cable, some rubber rings whose purposes I still don’t know, extra screen protectors, and papers. I especially like the little catalogue showing all the Shanling products. It reminds me of the catalogues coming with Lego sets, instilling the desire for more even though you are yet to finish the current set.



M6U is a solid chunk of metal and glass. It feels hefty and well-constructed. When I gave the DAP to the staff at a local hi-fi store for inspection, their first impression was, “it feels like an Astell & Kern (A&K).” Having used the SA700, I still think A & K DAPs are better built, but the difference is slight. M6U feels more substantial in hand than Fiio M11+.

On the right side of the device, you have a clickable volume wheel that also serves as a power button. On the right side, you have the usual playback control buttons. At the top, you have 3.5mm and 4.4mm outputs. Even from the appearance, you can already guess that the 4.4mm output is the favoured one with the golden ring. At the bottom of the unit, you have a USB-C connector and micro-SD card slot.



M6U is chunky but not a large device. It is as wide as my iPhone XR and around half a thumb shorter. The thickness of M6U easily doubles my phone. It is almost the same size as a battery-powered DAC/amp unit like Topping G5. It absolutely dwarfs dongles and pocketable DAP like Hidizs AP80 Pro X.



M6U is an ergonomic device. My fingers naturally fall in the curves of the metal frame, locking the DAP securely in my hand. All the buttons and wheels are easy to reach regardless of whether I use my left or right hand. My only complaint is that the wheel can rotate when I slide the DAP into my pocket. This problem can be alleviated by using the official leather case, which is, unfortunately, a separate purchase.

Screen, Software, BatteryPermalink​

The screen is perfectly adequate for the purpose of browsing music and even consuming media. It has a wide viewing angle, with good colour and contrast. I tried some YouTube videos with M6U and have nothing good or bad to report about the screen. In a side-by-side comparison, it is more or less of the same quality as my iPhone XR. The screen is bonded to the front glass, just like new iPhones and high-end iPads, as there is no gap between the screen and the finger touch.

The software is almost vanilla Android 10, devoid of bloat apps. Out of the box, you have the Shanling music player app, another Shanling app for OTA updates, a couple of app stores, and a rudimental web browser. I got Apple Music on M6U in five minutes without logging into my Google account.



The real power of M6U’s software is a feature called Android Global Lossless Output (AGLO), which is baked into the custom Android version used by Shanling. Simply put, the Android operating system resamples your audio before outputting it to your dongle. A few music player apps, such as UAPP, HiBy, and FiiO, can take control of the Android’s audio stack to output bit-perfect audio to your dongle. The AGLO feature of M6U ensures that every application, even Apple Music and YouTube, can output bit-perfect audio, bypassing the limitation of Android.

An advantage of AGLO is that you can use whatever music player app you want without losing fidelity. And this is good because Shanling’s music app still does not support gapless playback.What does that mean? It means that when I listen to Goldberg’s Variations, for instance, there is a gap between variations even though they are recorded continuously in one take. Such gaps ruin this recording for me. Luckily, I can swap Shanling’s music app with Fiio’s (as per Shanling’s suggestion). Of course, you can easily use EQ applications such as Wavelet and PowerampEQ.

The battery run time of M6U is okay, but it does not instil a lot of confidence. Even on low gain, I can feel the device heating up (not scorching hot, just warm), and I can see the battery percentage dropping. Still, I think the “lack of battery life” is more psychological and physical. The device can make it through a workday with enough battery to listen at home for another hour or two.

The standby battery life, on the other hand, is stellar. Recently, I left M6U in my drawer for nearly a week as I was busy testing another device. When I picked up M6U, the battery was still exactly how I had left it at around 50%. I was able to use it for another workday before having to charge it.

Various use cases of M6U​

You can use M6U in a few ways:

• A music player for your FLAC or MP3 music collection.
• A music player for streaming from Apple Music, Spotify, Tidals, etc.
• A USB DAC/amp device for your laptop. I used M6U for zoom calls from my laptop once in a while. It’s perfectly alright, though I detect noticeable audio delays with YouTube videos
• A music source for your hi-fi setup. I sometimes connect M6U to my two-channel setup at home via an aux cable (3.5mm to 3.5mm).
• A Bluetooth receiver. For instance, I can connect M6U to my phone via Bluetooth to watch YouTube videos and hear the sound coming from M6U.
• A Bluetooth transmitter. For instance, I can connect M6U with my wireless earphones or headphones.
• A music source for your dongle or portable DAC/amp. For instance, I can connect USB dongles that I review directly to the USB-C port of M6U and use the same music collection to do A/B tests. This capability opens the ability to use M6U with external DAC and amps. However, I cannot understand the point of getting an M6U (expensive) to do something that any affordable Android phone can do.

Sound Performance​

Gears for A/B tests:

• Moondrop Blessing 2 (22ohm, 117dB/Vrms)
• Fiio FF5 (45ohm, 108dB/mW)
• Campfire Audio Andromeda 2020 (12.8ohm, 112.8dB/mW)
• Final Audio E5000 (14ohm, 93dB/mW)
• TGXear Serratus (300ohm)
• Apple USB-C to 3.5mm dongle
• Hidizs AP80 Pro X
• Hidizs S9 Pro
• Topping G5
• Fiio K7

Playlist for A/B tests: IEGems Playlist

Sound overview​

The first time I listened to Shanling M6U, I told myself: “hmm… interesting.”

Not an “oh yeah!” or “uh oh…” It was just simply … interesting.

The reason was the so-called “Shanling house-sound” tuning. M6U puts extra weight on the low end of the frequency spectrum. At the same time, it shaves off some of the abrasiveness and sibilance of the high notes. The midrange also feels thicker and slightly highlighted. As a result, M6U puts a pleasant, warm tint over the stock tuning of all of my transducers. Even though the effect is less heavy-handed than an EQ profile, the difference struck me immediately upon the first song, without waiting for extensive A/B tests.



Let’s take the Presto movement of Vivaldi’s Summer as an example. With the TGXear Serratus (300ohm earbuds) and Hidizs S9 Pro dongle, I hear a bright, brilliant, but also slightly thin and piercing violin. The cello at the front-right of the stage sounds correct, though slightly lacking warmth and rumble. When switching to M6U, I hear a noticeable improvement in the weight of all string instruments. The cello has more resonance, thickness, and bass rumble. When the violin reaches a high note on the E-string, the random piercing sounds are also noticeably reduced. I found this tonality changes pleasant or “musical.”



Another advantage of M6U is soundstage imaging. Similarly to other battery-powered DAC/amp units and desktop setups, M6U is adept at expanding the soundstage in all directions, reducing the risk of instruments meshing into blobs. Due to the Shanling house sound tuning, the soundstage also has an extended sense of depth and layering. For instance, M6U places the cellos in Presto on my right, further toward my shoulder rather than at the front-right angle.

Another exciting thing about M6U’s soundstage is the illusion of height. I often hear cymbals and chimes floating above my ears, close to my head. Vocals can float above my forehead depending on the mix and mastering techniques. All and all, exciting and thoroughly satisfying soundstage imaging.



Another advantage of M6U that I did not expect is the improvement in micro-details compared to dongles and micro-DAPs like AP80 Pro X. These differences are apparent with old CDs such as Goldberg Variations performed by Glenn Gould or the complete sonatas and partitas recorded by Itzak Perlman, where the micro-details (room reverb, resonance of the piano, bow catching strings, fingers tapping on the fingerboard) are not highlighted. With AP80 Pro X, I mostly hear the musical notes and not much else, so the experience was a bit bland. With M6U, I hear an increase in the richness of details around the notes. Suddenly, it’s not just Perlman or Gould playing the instruments. The reverb of the recording hall and the resonance of their instruments provide additional harmony to the sparse and contemplative music.

Of course, you don’t have to listen to classical music to enjoy the improvements of M6U. Even commercial music sounds punchier, easier on the ears, and richer in detail.

Before we move on, let’s address the elephant in the room. If the tuning of M6U is so pleasant, can’t we copy it with EQ? I wish it were that easy. I spent days trying to emulate the sound of M6U with the powerful PEQ feature of my AP80 Pro X to improve the little DAP, yet I could never quite get there. My adjustment was always not enough or too much. When I managed to match one song closely, the other songs sounded off. The soundstage imaging is also impossible to copy. From what I gathered, the difference is due to a skilful mix of harmonic distortion in the sound. Such “boost” would move around depending on the content of the music. Thus applying a fixed EQ profile wouldn’t be able to replicate.

Average IEM and earphones (5/5)​

Average IEMs and headphones are the ones that fall within the sweet spot of the amplification circuit inside the Apple dongle. Because these IEMs and headphones are adequately powered by an Apple dongle, swapping the dongle to a better source tends to provide limited improvements. Therefore, the first test for any source coming to my review table is “how much can you improve a typical IEM?”

I rely on Moondrop Blessing 2 and Fiio FF5 earbuds for this test. As I described above, M6U noticeably outperforms good dongles such as S9 Pro, which exceeds the Apple dongle.

The remaining question is whether M6U can match a sensible desktop setup, such as the Fiio K7.

Yes.

The expansion of the soundstage is on the same level. The micro-details are on the same level. The only difference between M6U and K7 is, again, the Shanling’s house sound, which tends to shape the soundstage as a dome. K7’s soundstage is less “around the head” but projected a bit further in front of me.

Since M6U handles average IEMs as competently as my desktop setup, and I personally consider desktop-level performance as excellent (5/5) for portable gears, I rate M6U as 5/5 on this criterion.

Low-impedance, high-Sensitivity IEM (4.5/5)​

The next test is with the hypersensitive and notoriously picky Campfire Audio Andromeda 2020. You might think Andromeda is easy to drive because it has low impedance and high sensitivity. However, that’s not the case:

1. They hiss on many audio sources, negatively impacting their technical performance.
2. They get loud quickly, so most dongles are too loud, even at the lowest volume.
3. Because of their low impedance, they can be demanding in terms of output current.

In fact, the Apple dongle must be turned to nearly 50% to reach a reasonable listening level. Even then, I don’t think Andromeda reveals their full potential.

M6U handles Andromeda very well, but only via the single-ended output. I detected slight hissing noise when using Andromeda with the balanced output.

Regarding the sound quality, M6U makes the soundstage more spread out and 3D compared to S9 Pro with both G.O.A.T. and Presto, my favourite test tracks. Interestingly, the BA bass of Andromeda becomes a bit more potent with M6U and K7, compared to S9 Pro. I did not expect to hear the noticeable difference, so I was surprised.

The most significant improvement of M6U is actually the volume control. With S9 Pro, I’m stuck at around 2/100 listening to G.O.A.T., meaning I cannot reduce the volume any further. With M6U, I listen at about 16/100, meaning I still have a wide range of adjustments.

Due to the hiss with balanced output, I rate M6U as 4.5/5 in driving sensitive IEM. It is not 4/5 because that score belongs to S9 Pro, and Andromeda sounds noticeably better with M6U than with S9 Pro.

Low-impedance, low-sensitivity IEM (5/5)​

E5000 is a stubborn IEM. Low impedance, low sensitivity, and significantly bass-boosted make a nasty combination. You can get the midrange 1kHz region loud with even an Apple dongle. However, the bass would become a muddy mess, making the E5000 blunted and fuzzy. That’s not how these IEMs should perform. A fully powered E5000 is a bass-head dream with an overwhelming bass response and smooth treble that allows you to keep turning up and up to soak up that bass. The midbass itself is tight, not muddy or pillowy. The sub-bass digs deep and rumbles hard.

M6U handles E5000 very well, even using the single-ended output. I needed only 45/100 in low-gain mode to listen to G.O.A.T. The improvement upon S9 Pro is immediately noticeable in back-to-back A/B tests. M6U presents G.O.A.T. with more space, more separation, and more layering. M6U tucks bass toward the sub-bass, creating distinct punches and rumbles rather than a muddy “ummm” mess that weaker sources might run into.

M6U sounds almost identical to K7, despite the difference in the tuning.

In summary, 5/5.

High-impedance earbuds (5/5)​

As I described earlier, M6U drives high-impedance loads such as TGXear Serratus earbuds (300ohm) without a sweat. The earbuds get loud with classical recordings, even at 40/100 in low-gain mode.

Using Presto as a test track, I hear a soundstage as extensive and detailed as the K7 on M6U. However, a distinct added “weight” is added to the bottom end of the frequency spectrum. The violin still has brilliance and brightness but is slightly rounded off when reaching high notes. The difference is quite noticeable. Whether M6U or K7 is better would be a matter of reference.

In summary, 5/5.

Life with a DAP​

As we reach the end of this review, let’s go back to the opening question: “What’s the point of digital audio players (DAP) in this day and age?”

From a pure performance/cost ratio perspective, No, there is no point.

But it does not mean that a DAP is not desirable. A device like M6U is a desktop setup you can put in your bag or pocket. From the convenience perspective, there is a sense of freedom when you don’t have to deal with separate devices, cables, and Bluetooth in your listening session. You pick up the brick, your IEM or your headphone and enjoy.

There is also a psychological perspective. As someone who is easily distracted, having a brick dedicated to music helps me to focus on the thing for which I buy all these gears: enjoying music. Not just playing music in the background but savouring it. Of course, a phone and a dongle serve the purpose just fine, but a dedicated brick feels better (to me).

Should you get an M6U? It depends on how much you want a music brick. If you’ve decided that you want one, despite the performance/cost argument, then Shanling M6 Ultra should be one of your options. It’s a good one.