Sony NW-A55 DAP

kmmbd

500+ Head-Fier
The Rebirth
Pros: Sleek design, and excellent build and ergonomics
- Clicky buttons are easy to find by touch
- High resolution display has good contrast
- Handy DSP tuning options
- Superb battery life
- LDAC support with stable Bluetooth connectivity
- Modded firmware brings the tuning of flagship Walkman players at a fraction of the cost
Cons: Display is dim, poor legibility under sunlight
- Proprietary WMPort for charging and data transfer
- No streaming app support
- Sound without modded firmware is uninspiring
- Low output power, not for high impedance loads
- Hiss with sensitive IEMs
- Limited availability, discontinued in many regions
Sony A55 - Display.jpg


Sony’s Walkman line of music players are legendary. I myself grew up with a Walkman cassette player and have fond memories of listening to several “best hits” mixtapes. Those were the days, huh?

Sony’s NW-A55 Walkman DAP brings back nostalgia while incorporating some modern features. That being said, the out-of-the-box experience is merely average at best. Released in 2018, it lacks some modern features like WiFi connectivity, type-C port etc.

Only when you get into tweaking does the A55 reveal its true prowess.

Disclaimer: I purchased the Sony NW-A55 with my own funds.
This review originally appeared on
Headphonesty.
IEMs tested: Final E1000/E3000/A3000/A4000/ZE3000, Dunu SA6/Zen/Titan S,

In the box​

The box basically has the WMPort charging cable inside and nothing else. So not much in the way of accessories, which is disappointing.

Design​

Sony absolutely nailed the industrial design with the NW-A55.

The candybar shape with rounded sides and flat corners make the A55 a joy to hold and operate in one hand. The buttons are also conveniently placed and can be distinguished with the device in a pocket.

Sony A55 - Buttons.jpg


Speaking of the buttons, they are placed on the right side of the device. The volume up and pause keys have raised “nubs” to distinguish them while in the pocket. Moreover, the buttons have differing sizes and shapes based on function (e.g. playback buttons are circular whereas volume buttons are rectangular). Sony’s attention to detail shines here.

Sony A55 - Card slot.jpg


The left side of the device houses the microSD card slot. The top side is bereft of controls or ports. Instead, the bottom of the device has all the ports: 3.5mm output jack, lanyard eyelet, and the notorious WMPort.

Sony A55 - Ports.JPG


Display​

Measuring 3.1” diagonal, the NW-A55’s display might seem small by modern standards. However, given the overall footprint of the device and its intended function, this display size is absolutely fine. The display is very sharp with 300ppi pixel density.

Sony A55 - UI.JPG


Sony did not put any anti-reflective element under the display and this results in severe loss of contrast, especially in bright sun.

Usability​

The NW-A55 is as ergonomic as portable audio players get. It’s lightweight, but doesn’t feel “hollow”. It has the perfect shape for one-handed use, and Sony’s UI is customized to make the best use of limited screen space.

User interface​

Sony’s proprietary UI can be navigated via swipes and the navigation bar at the bottom of the display. Swiping up from the playback screen shows the various DSP and sound effect settings. I personally keep “Direct Mode” turned on which disables all DSP and renders a reference sound.

Sony A55 - Tuning.jpg


The NW-A55 can also act as an FM radio tuner, and Sony’s hardware FM radio chip results in excellent radio reception. The BT sink function allows you to pair your phone with the A55 with the DAP acting as a Bluetooth dongle. Moreover, you can use the NW-A55 as a desktop DAC as well, though this requires software installation and there is some lag at times during playback.

Overall, it has a mostly logical UI layout with some expected oddities. You won’t need to refer to the manual to operate the NW-A55, and that’s a triumph on Sony’s part.

Battery life​

Battery life is excellent (20-45 hours depending on music file types and settings) and I usually have to charge it once every two weeks. This is a combination of the low output power, small display, and Sony’s frugal operating system. Recharge times are long, with approximately 4 hours needed for a full charge.

Internals​

Sony keeps their proprietary tech shrouded in mystery.
Most of the time you get some cool-sounding acronyms and marketing jargon instead of a detailed technical breakdown.

For the NW-A55, no information about the DAC chip is provided and the amp section is only referred to as “S-Master HX”. Digging deeper, I found that Sony uses an IC called “CXD 3788GF” that acts as the “digital amplifier”.

During operation, the amp section acts as a class-D amplifier with the output of the IC being a Pulse-Density Modulation signal (PDM) instead of the traditional Pulse-width Modulation signal. There is also no negative feedback-loop in the amp section and Sony claims that this improves sound.

The DAC chip is reported to be FPGA-based and it’s due to the efficient DAC chip and low-power amp section that the battery life on the A55 is phenomenal. Sadly, I could not find much implementation details on the DAC side, or how the PDM signal is amplified to the output stage.

Sony NW-A55 Sound​

Depending on the firmware installed, the NW-A55 can drastically alter its sound signature.
Even ignoring the myriad of DSP tunings, the NW-A55 can be made to sound “different” based on the firmware version installed (official or modded), and even the region selected.

Stock firmware​

In stock form with all effects turned off, the NW-A55 has a warm-neutral signature. There is some roll-off in both the sub-bass and upper-treble frequencies even though it’s nothing significant.

Bass notes are somewhat soft and rounded in this firmware and the staging is about average. Overall, an inoffensive, if uninspiring sound signature. The NW-A55 in its stock form does not stand out in any way, and that’s the biggest downside and the greatest motivation to investigate the custom firmware route.

MrWalkman firmware​

Before proceeding with this section, please note that installing custom firmware may void your warranty or potentially render your device unresponsive. The user assumes all risks of installing the custom firmware and must read the instructions carefully.

With that disclaimer out of the way, let me introduce you to the wonderful world of MrWalkman. MrWalkman is a modder who makes custom firmware for a lot of the non-Android Sony DAPs. The purpose of his firmware it to get the sound of higher-tier Walkman DAPs on a budget. Check out his wonderful head-fi thread for information regarding latest developments.

Sony A55 - Custom.jpg


Given that most of these DAPs have internal similarities, the end result is tantalizingly close to this lofty promise. For example, installing Midnight V2 firmware on my NW-A55 made it sound surprisingly similar to the flagship Sony WM1A.

Now, the technicalities on the WM1A are far ahead of what the A55 is capable of, and so is the amplification power. However, some of the highlights of the WM1A are present on the A55 after this mod, e.g. spectacular vocal layering.

The latest update to the custom firmware scene (Walkman One) brings four different tunings in one package. The user can choose between various signatures based upon the IEM pairing. E.g. Neutral mode for reference sound, or “WM1Z” option for a sound signature akin to the venerable Sony WM1Z.

Sony A55 - WM1A.jpg


These mods also add extra features to the UI, for example a VU meter that is usually unavailable on the NW-A55, and extra DSP effects or modes.

So if you are feeling adventurous enough, go ahead and install the custom firmware, assuming all the risks of course. I personally found the installation process fairly simple, and reverting to stock firmware literally takes only two clicks.

For the installation process, please refer to the FAQ section on MrWalkman’s website. Bon voyage!

Pairing Notes​

The NW-A55 is only suited for moderately sensitive, low-impedance IEMs and headphones. Using high impedance IEMs or headphones like the Sennheiser HD560S (120 ohms) results in a muddy and muted sound. Meanwhile, low sensitivity IEMs like the Final E4000 (97 dB/mW) demand the volume to be pushed much higher and you end up not having much headroom.

Another potential issue can be hiss with extremely sensitive IEMs. Both the Final FI-BA-SS (112 dB/mW) and the Campfire Andromeda (113 dB/mW) exhibited hiss and elevated noise floor. Granted, once the music plays you do not notice this, but during quiet passages it is noticeable. I will recommend using IEMs or headphones with sensitivity between 100-110 dB/mW and nothing more than 32 ohms.

Fortunately, the vast majority of IEMs released fall within the “operation limits” of the NW-A55, so it’s not all bad news.

Comparisons​

Vs Hidizs AP80 Pro​

The Hidizs AP80 Pro is priced a bit lower than the NW-A55 and is another favorite DAP of mine. I like the size, design language, and the bright display. The touch-based Hiby OS is also easy to navigate, though animations can get choppy.

IMG_1027_1080.jpg


In terms of build quality and ergonomics, I give the nod to the NW-A55. The Sony DAP is more comfortable to hold and doesn’t attract smudges like the AP80 Pro. General UI features are fleshed out on both. AP80 Pro has some added features like step counter and ebook reader whereas the NW-A55 has more interesting DSP effects.

AP80 Pro has MSEB (Hiby’s DSP engine) but the implementation on the AP80 Pro does not sound as pleasing as on Hiby’s high-tier DAPs. Also battery life is far superior on the NW-A55. The AP80 Pro has better connectivity, however, with the type-C port being a lifesaver.

Additionally, the AP80 Pro is better as a DAC because it doesn’t lag with high bit-rate or DSD files when connected to a Windows PC, and it has a proper line-out with fixed voltage (2Vrms) for connecting to an external amp.

In terms of sound, I prefer the tone of the modded NW-A55 (especially the WM1Z tuning from the custom firmware). The tonal richness and layering is better on the Sony DAP. The AP80 Pro has excellent separation and resolves as well as the NW-A55 but the mids do not sound as engaging. AP80 Pro does have more output power, a balanced output, and barely hisses with sensitive IEMs.

Sony A55 - Cover 2.JPG

Conclusion​

Sony’s NW-A55 is a hidden gem and it ticks most of the important boxes for a DAP: excellent design and ergonomics, class-leading battery life, sharp display, and a pleasant tuning that can be altered according to taste.

Caveats apply though, as modding or installing custom firmware won’t be everyone’s cup of tea. That being said, the Sony NW-A55 has aged gracefully and seems to get better with every custom firmware release. Even after four years since the initial launch, it’s pulling out new tricks from its sleeve. In the age of rapid-fire releases from manufacturers, this change of pace is very welcome.

The custom firmware is the sole reason one should get the A55.

The Sony NW-A55 earns my heartfelt recommendation as the most fun I’ve had with a portable audio player in ages. If you can find one around, that is, which is a crying shame.
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Redcarmoose
Redcarmoose
Nice!
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Peddler

1000+ Head-Fier
Wonderful little player with some nice features.
Pros: Lovely sound. LDAC Support. Genuinely useful features. Compact Size. Good battery life. Fast NFC pairing.
Cons: Sony specific cable. Not as powerful as some others.
Well made, inexpensive and sounds great.

Well I have to admit that this is the first completely unjustifiable purchase I have made in quite some time. Firstly, I tend to do a lot of my listening with bluetooth headphones which really don’t offer any sound quality differences between different players - assuming they’re using the same codec of course. Secondly, I spend more and more time listening to streamed content (usually Google Play Music) and am pretty much satisfied with its sound quality. Thirdly, I pretty much always carry my phone around with me (kinda like everyone else on the planet) and so always have access to not only my personal music collection on Micro SD card but also the before mentioned streamed content. So why the hell would I want to drop nearly £200 on a dedicated MP3 player which, apart from its small size, brings almost nothing to the table when compared to my smartphone?

Well…..if I’m going to be utterly and completely honest - because I wanted to. Secondly though I recently got sent a pair of Fiio’s rather excellent FD-1 wired IEMs and suddenly became ‘woke’ again to the joys of higher resolution music. My phone is the Samsung Galaxy Note 8 which is not renowned for sound quality through the headphone jack. Strangely I recently changed it from the LG V20 which is the complete opposite - having superb wired headphone output. The truth is that Samsung has much MUCH better bluetooth capabilities and I have an external wired DAC/AMP which I can connect to the phone for that ‘high-res’ experience.

In my defence, there were some other reasonably effective rationalisations that I employed in order to mentally justify the expense. The player has excellent battery life (unlike the NW-A105 which I was very tempted to get), and can act as an external wired DAC and wireless bluetooth ‘amplifier’ - with the ability to control the streamed content with the players own external media controls. This effectively means that I don’t have to worry about not being able to stream Google Play Music from the device directly (no wifi) but rather tether it to my phone’s LDAC bluetooth output and really have the best of both worlds. Excellent battery life in a very small package but also capable of replicating many of the features found in the NW-A105.

So how is the Sony NW-A55? There’s plenty of YouTube videos showing the unit off so there’s not much point in going into too much detail regarding the externals - I really want to focus on the features and sound quality elements.

Useful Features

There were a couple of features I read about on this player which effectively tipped my hand - the external DAC/AMP function and the Bluetooth receiver. I think I will definitely make use of both these features. The bluetooth receiver function works brilliantly with my Galaxy Note 8. It connects using the LDAC codec to the sound quality is excellent. I have the Axium Aqua + bluetooth amp and this sounds better. LDAC really does make a difference.

20200717_220444.jpg


The NW-A55 also offers LDAC bluetooth output to compatible headphones - and this sounds really good. My WH1000XM2’s connected using the NFC function seamlessly and the connection was rock solid with much better range than what I get on my phone - and…..I really don't want to say it but they actually sound better as well. There’s significantly more volume available when using bluetooth headphones. Unfortunately the same cannot be said when pairing up Sony’s latest WF1000XM3 bluetooth noise cancelling earbuds as the A55 doesn’t support AAC - only SBC and APtX/APtX HD and LDAC - so the WF’s only connect via SBC. Whilst they don’t sound too bad, they definitely sound better when connected to my phone.

Another really useful feature is the external playback controls. Basically this allows you to operate the device without having to take it out of your pocket. Another useful advantage to these is that you don't have to activate the screen every time you want to switch tracks or increase/decrease the volume - this can really help increase battery life.

It can act as an external DAC/AMP for laptop/desktop computer use. This has effectively given the A55 most of the advantages that the A110 would offer without the disadvantages (crap battery life and limited headphone output). I can use my Galaxy Note 8 to stream from Google Play Music to the A55 via bluetooth using the LDAC codec. Although this may sound like a bit of a faff it’s really not that difficult and only takes a few seconds to set up. The end result definitely sounds better than the headphone output from my phone’s headphone socket. You can’t use bluetooth headphones when doing this - in all fairness you would simply connect your headphones to the phone instead of the player under these circumstances.

Sound Quality

This is always a subjective thing in my opinion - bear in mind that I'm an old dude and my taste in music is somewhat varied. First things first - the volume issue.

My player is (or was) EU volume capped which limited the output. I do like my music fairly loud a lot of the time and I have to say that I really didn't have any problems in getting the volume levels I wanted. Headphones used include the Ultimate Ears Triple Fi 10, Fiio FD1, Sennheiser HD598SR, Sony WH1000XM2, Mavin Air-X and the Sony WF1000XM3's. Even the Sennheiser's got pretty loud - admittedly I could have coped with a little more. However, after un-capping the EU Volume restriction the 598's can be driven uncomfortably loud now. The most impressive results I got were with the IEM's (except the Sony WF's) and the WH1000XM2's. The pairing of this player with the Sony WH's is a match made in heaven. They really open up nicely and wow - they go really REALLY loud! I like the Sony 'house' sound. It's not afraid of showing a little grunt in the low end whilst still being polite and controlled. Whilst the various EQ/Sound Shaping functions are quite impressive, I tend to always listen with all these bells and whistles switched off. I feel this offers more resolution in the mids and highs too. Even when pushed hard, these headphones remain in control and rock out.

Bluetooth range and stability are first rate too. I am able to travel much further away from this little MP3 player than I ever could with my phone. Gardening (with lovely active noise cancelling) is going to be a lot easier without having my bulky phone sticking out of my pocket. I love it!
The more I think about this the more I feel that this is the last of Sony's sensible players. All their players further up in their price range all tend to have some serious shortcomings - typically battery life, limited headphone output and/or excessively bulky/stupidly expensive. Whilst it would have been nice to have Wi-Fi - this would require the Android operating system in order to make the Wi-Fi worthwhile by allowing you to run your own favourite music applications. The end result is appalling battery life. The A55's solution through Bluetooth pairing to your phone is a really nice touch - definitely a smart way of overcoming this limitation.

In case you haven't guessed it by now, I really like this player. It's the best sounding player I've ever heard - here's a list of some of the players I've had in the past:-
  • Sony Discman 555
  • Sony Discman D350
  • Sony Minidisc - MD1, MD900 MD R35
  • Creative Nomad Jukebox 3
  • Apple Ipod 1, 7
  • LG V20
Trust me when I say that the list is embarrassingly incomplete - I've spent bloody thousands of pounds over the years on music playback. Wow - I could have bought a bloody Jag.

This player ticks an impressive amount of boxes - one that's perhaps overlooked by many though is how long this player could theoretically last - the rather excellent battery life means that you don't need to charge it very often which will result in the player lasting a good time longer. To give you an idea of just how impressed I am with it, I'm seriously thinking of buying a very large Micro Sd card and storing all my music on it.

For a player which has a reputation for being low powered, the NW-A55 hasn't had any problem driving all the wired and wireless headphones in my collection. Whilst the Sennheiser HD598SR requires nearly full volume, it still sounds powerful and effortless - and absolute full volume is actually uncomfortably loud. The sound character is detailed and full sounding. I'm reminded of the first time I heard the Etymotics ER4P - the amount of detail and the rock solid imagery was unique. It was easy to choose a specific instrument for example, and follow it throughout a track without even having to concentrate. The NW-A55 definitely has this characteristic. It's a player that's easy to listen to and tends to make the most of any headphone that you connect to it. There is one exception though and that is the Sony WF1000XM3's. As it is I have paired my rather excellent Lypertek Tevi's to the Sony and, again I have to say it, they sound better than through my phone. So now I have (in my opinion) a really nice ultra-portable (Tevi's), portable (WH1000XM2's) and at-home (Sennheiser HD598SR).

I love this little player. Sony have gone and got so many things right with it. No distractions with other apps, superb connectivity options (we all have Bluetooth enabled smartphones don't we?), really REALLY good sound quality, excellent battery life (which ensures genuine longevity) - the list can go on. I'm so glad I got the A55 instead of the A110.

Update

Thanks to the magic of Mr Walkman - the A55 can be 'flashed' with a kind of firmware update which brings some of the sound character and quality from Sony's top MP3 player (to call it that really doesn't do it justice) - the legendary DMP-Z1. This has elevated the sound quality to another level altogether. Highly recommended.
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BenGast
BenGast
I have had the player for 2 weeks and I am very happy with it. It is dealing very well with my 450GB lib.
joydivisionnewdawnfades
joydivisionnewdawnfades
Very great review!which one do you recommand (for the firmware)?The W1MA or the DMP-Z1 mod?
Peddler
Peddler
Your music has to be stored in a folder called MUSIC but after that you can use sub folders for individual artists etc. I'm using the DMP Z1 rom to good effect
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