The HUM Pervasion is a new kid on the block in the rapidly crowding world of digital audio players (DAPs), particularly those coming out of China (and in this case a Hong Kong company with manufacturing in China). To make any noise (pardon the pun) in this market a DAP needs to be very good. Luckily, the Pervasion has a few tricks up its sleeve to compete.

This has been one of those reviews that was a journey in itself to write. The more I listened to and used the Pervasion, the more questions it created. I’ve attempted to ask and answer all those questions here for you so please, strap in, relax, and enjoy the read!

EDIT: Please note that my Pervasion was returned to HUM for an update to bring its performance in line with final production versions. I have written an HUM Pervasion Update to clarify how it changed and improved.

Overview

The Pervasion looks like an old smartphone which is appropriate because it also runs Android software so you’ll probably have flashbacks to an original HTC or similar phone when you first pick up the Pervasion, but that’s not a criticism – it’s kind of fun and comforting.

Specifications

• Display:  4.3″ touch screen
• CPU:  28nm A9 dual core 1.2GHz
• OS:  Android 4.2.2
• Memory:  external only, up to 128Gb microSD card (FAT32)
• DAC:  Wolfson WM8741
• Op Amp:  LME49720 (used as a filter in the DAC stage)
• Battery life:  approx. 6 hours (full charge in 2 hours)

Much of the technical information about the Pervasion looks excellent on paper, but doesn’t guarantee great sound, however HUM’s emphasis on using a flagship DAC (Wolfson WM8741), high voltage power supply, and top quality components from the likes of Vishay, Elna, Alps, and Nichicon suggested an attention to detail and desire for quality. The question is, did they put all of these pieces together well or is the Pervasion just a mash-up of great parts that don’t necessarily synergise? At a rough price point of around $350 USD it could go either way… either amazing value or mediocre insignificance.

Design and Interface

I already mentioned that the Pervasion looks and feels a bit like an old phone, but for a dedicated audio player, that’s fine in many ways. It’s thicker in the body than a modern phone, but that’s most likely due to the extra audio components required to make the Pervasion sound like ‘not a phone’.

The chassis and casing of the Pervasion isn’t anything special. Putting it up next to the likes of the Shozy Alien, FiiO X5, or any of the Astell & Kern players, the Pervasion is going to look a little bit average. It’s not cheap or flimsy by any stretch, but it also doesn’t scream top-end quality. Don’t let that put you off though… you’re buying a DAP, not a showpiece. The chassis is everything it needs to be – it’s painted in a beautiful metallic red finish and it feels great in the hand. All the edges are well finished and the screen is a great size and has good clarity and vibrancy, especially for a music player.

Physical Controls and Connections

The top of the player has a micro USB socket for charging and data, and a simple on / off button which also wakes the device with a short press. On the left side (looking at the screen) is a simple up / down button for the volume and on the right side of the player is a slot for the microSD card which is uncovered, but cleanly finished and the card sits flush when installed so it’s a nice design – simple to access, but clean and neat. So far so normal, right? Let’s get to the stuff that you’ll never find on a phone…

On the bottom of the Pervasion you’ll find a pair of 3.5mm sockets – headphone out and line out – and a small, black volume wheel. “But wait”, you say, “Isn’t there a volume rocker on the side?” Yes there is, but you’ll want to use the bottom one most of the time. You see the WM8741 DAC chip (Wolfson’s top of the line) has digital attenuation, but it will degrade the sound quality by reducing the bit-depth of the signal. What this means in general terms is that as you reduce the volume level using the digital control, the distance between your music and the underlying noise gets smaller and smaller. You can actually hear this in action if you lower the digital control a fair way and then boost the analogue control – things get pretty messy at the extremes. However, if you leave the digital volume at full (255 / 255) you get pure, unadulterated audio to the internal amp and to the line-out.

Dual Volume Control is Awesome

In case you were thinking that this whole dual volume control thing was a bit dodgy, let me explain some great benefits.

Firstly it means you can adjust the line-out volume. If there was no digital control you’d have no way to adjust the line-out level and although significant reductions in digital volume bring noise issues, slight reductions in the digital volume won’t have an audible impact so you can use the Pervasion’s digital control to shave off a few dB if you need to for an external amp or a set of active speakers.

Reason 2 that the digital volume control is great is that you can run the line-out and the headphone out at the same time and adjust the volume of the headphone out without affecting the line-out volume. This means you can use headphones from both an amp and the Pervasion at the same time which, although rarely necessary, can be a handy trick.

Before I discuss the interface and sound quality, here’s a quick unboxing video so you can see the device “in the flesh” and also witness the beautiful startup animation:

Android OS

Running Android means that the Pervasion instantly becomes the perfect audio device in terms of interface. The processor in the Pervasion has the grunt to run Android smoothly, if not quite as snappily as a current smartphone, and the Android interface is smooth, polished, and allows you to run a variety of players like Neutron, PowerAmp, and PlayerPro (my app of choice).

Note: please don’t judge the quality of the Pervasion’s display from these pictures. I hope to provide a video soon which will better demonstrate the display quality.

Looking at the market that the Pervasion is competing with, there is a list of gripes with many of the modern, non-Apple competition (and let’s face it, Apple’s products, while great don’t really compete at this level at this time). The list of common gripes looks something like this:

• No ReplayGain (volume levelling)
• No gapless
• Crappy EQs
• No L/R balance control
• No crossfeed control (system for reducing the drastic and sometimes fatiguing separation created by headphones)
• No playlist support
• No CUE support
• Clumsy browsing
• Slow library scanning

Well, with the simple stroke of Android genius, the HUM team obliterated this list. Android and the associated apps I mentioned above handle audio perfectly. There is literally not a single feature or operation that is lacking from the Pervasion thanks to its use of Android. As I mentioned, my player of choice is PlayerPro, but many of the Android players offer great usability and full audiophile feature sets. There is literally nothing that the Pervasion lacks when it comes to interface features for a DAP. It’s beautiful with clean displays of album art, EQ settings, menus, and options. It also provides the ability to download album art and lyrics on the fly (if your Wi-Fi is strong) and even adjust the gain levels in the software realm where quality can be maintained 100%. The versatility of the Android system and therefore the Pervasion is seemingly endless.

Other Hardware

In addition to its audio hardware, the Pervasion does also carry Wi-Fi and Bluetooth circuitry so you can download apps, stream audio via internet radio services (in theory), and share your audio wirelessly with a Bluetooth speaker, car stereo, or headset.

Wi-Fi

In reality, despite offering b / g and n grade Wi-Fi reception, the stability of the reception is a bit weak so you’ll need a strong signal to enjoy consistent connections to your router and the internet. If the connection is strong, everything’s fine – just don’t expect the Pervasion to compete with other smart devices – it’s an audio focussed device. With that in mind, you’ll probably also want to disable the Wi-Fi for serious listening session because it’ll drain the battery faster and it also creates some audible noise during moments of high traffic.

Bluetooth

The Pervasion uses Bluetooth 4.0 technology which shows that once again the HUM engineers didn’t cut corners in putting the Pervasion together. As the most current Bluetooth standard, 4.0 brings more efficient power usage which is key in a compact device running (relatively) high voltage audio circuits.

Pairing and interaction with Bluetooth devices is hassle free, but the listening to music is a bit of a mixed experience. While the screen is on and you’re interacting with the device the sound tends to be quite choppy and stuttery – unlistenable actually. When the screen is off, however, this problem goes away immediately. Interestingly, changing player software from PlayerPro to Google’s own Play Music app reduced the problem, but didn’t completely solve it so I can only assume there’s a problem with memory resources when the Pervasion is running both the screen interface and the Bluetooth circuit. The good news is that once you’re setup and going you won’t often be using the screen so the sound will be just fine when you’re actually listening. I personally wouldn’t buy the Pervasion as a Bluetooth audio device given that most phones on the market will provide a better experience and sound quality (via Bluetooth) that’s not far behind, but the feature is there if you need it.

Sound

The Pervasion is a dedicated audio device that happens to have various Android features, but it wasn’t built to be a smartphone replacement, it was built to sound awesome. Let’s take a look at how well it achieves the brief.

Format Handling

The Pervasion will run any format I have thrown at it including standards like WAV, FLAC, and MP3, but also extending to Apple’s M4A (AAC) format, Microsoft’s WMA format and OGG format too. Sound quality with all formats is excellent with no immediately obvious quality differences between high bitrate lossy files and lossless flac versions of the same. More critical listening may show some improvements with lossless formats, but the quality of the Pervasion’s decoding means that you have to listen for the differences and that’s great. The Pervasion won’t shred your ears with lower quality formats, in fact it will caress your ears regardless of the format provided it seems – there’s no judgement here, the Pervasion is happy playing whatever you feed it.

There is one small catch though… higher resolution formats aren’t always a good idea on the Pervasion. Technically speaking it does play them, but it does so with software decoding (basically down-sampling it) and there’s all kinds of noise created in the process depending on the sample rate chosen. The Pervasion is designed as a 16-bit player only so consider it as such, but here’s a summary of my hi-res experiences (using FLAC) with the Pervasion:

• 24-bit / 88.2kHz either doesn’t play or it plays with slight, but noticeable distortion to the sound that makes the music sound unnatural
• 24-bit / 96kHz seems to work fine
• 24-bit / 176.4kHz plays, but creates even more noticeable noise in the form of an electronic oscillation noise
• 24-bit / 192kHz seems to work fine

OK, so the most common hi-res formats of FLAC 24/96 and 24/192 seem to work fine, but there is absolutely no benefit and there may be drawbacks such as greater battery drain and possibly hidden noise which may or may not become apparent on different tracks. In short, I’d say to stick with standard “red book” (16-bit / 44.1kHz) files and save yourself some space on your memory cards for extra tracks. The red book audio quality is excellent so you likely won’t miss having hi-res audio on the Pervasion and there are plenty of articles out there about why hi-res may not actually provide any real benefits so rest assured that what you’re hearing from the Pervasion is already excellent without the need for space-eating hi-res formats.

Headphone Output

There are no power specs published for the Pervasion, but it has plenty of grunt for a compact portable device – that much I can say for sure. I’ll discuss a range of different headphone pairings shortly, but let’s start with the overall signature and quality of the onboard headphone amp.

First up, much like the Shozy Alien, there is a very slight background hiss when using sensitive IEMs that is particularly audible if the IEMs isolate very well. The hiss is very, very minor (slightly less than the Alien) – to the degree that slight background noise in the room completely hides the hiss – but it is there which is a shame. The good news is that it’s completely inaudible in most ‘normal’ situations (commuting, listening to music at moderate volumes, etc.) so it shouldn’t pose any major concerns to most people and certainly there are many Alien owners who have no problems at all with its slight hiss so I think this is just a case of me being hyper-sensitive to noise.

The sound from the Pervasion’s headphone jack is slightly warm – not at all bloated or thick, but slightly warmer than neutral. In fact, the Pervasion’s sound is almost identical to the Shozy Alien. There are slight differences in the mid-range and bass, but there are more similarities than differences and that’s great because the Alien sounds awesome so the Pervasion is instantly in great company. The bass is full and the treble is clean and well-extended, but smoother than offerings like the FiiO X5. Mid-range tones are rich and warm with good detail, in fact detail is probably the one area that the Pervasion sets itself apart from the lower-priced Alien. The sense of subtle detail and texture from the Pervasion is beautiful. It’s subtle enough that it won’t hit you at first, but over time you just keep hearing more and more of the hidden details in your music.

Over-emphasised detail can be fatiguing and distracting when you’re trying to listen to your favourite music so I love that the Pervasion just presents it (much like some of my other favourites, the Noble K10s and Shozy Alien) without shoving it in your face. With the Pervasion you can choose to get lost in the music or get lost in the details, but the choice is yours and I love that!

In terms of pure sound signature, the other thing that sets the Pervasion apart from the Alien is a slightly more prominent sense of treble extension and a slight lift in the lower mid-bass that gives the overall sound a nice fullness. To some people and with some ‘phones this might be bordering on too warm, but for most setups and most people the Pervasion will just sound really good – smooth and organic.

Placement of sounds and accuracy of the image is excellent. There’s also great space in the soundstage both in terms of width and depth. Just like the Alien, the Pervasion creates an immersive and engaging listening experience that never fails to be enjoyable while also being detailed and accurate. The stage is both wide and spacious, but more importantly it is coherent. I use the Dancing Flute & Drum track from Dr. Chesky’s Sensational, Fantastic, and Simply Amazing Binaural Sound Show album to test soundstage because it is recorded in a large open space and when the drum sticks are hit you can hear the sound echo out and around the room like a sonar. This test will really show if there are incoherencies in the presentation of soundstage, but I’m pleased to say that the Pervasion passes this test with flying colours, unlike the much more expensive RWAK100.

Specific Headphone Pairings

Noble Kaiser 10 (35 ohm): I feel like the Pervasion gets about 90-95% of the Kaiser 10’s full performance using the headphone output. The K10’s still sound exceptional as always, but I feel like the very slight colouration from the Pervasion prevents the pairing from reaching the peak sound that the K10s can provide. Of course, this is a matter of personal preference – I just happen to prefer the K10s from a slightly leaner source. The good thing is that all the details are all beautifully presented and the music is constantly enjoyable despite not being optimised to my personal tastes.

Shure SE846 (9 ohm): Despite also having a warm sound like the K10s, the SE846s (using the neutral, blue filter) pair really well with the Pervasion. Somewhere in the frequency response of the SE846 is a small lift which matches beautifully with the Pervasion’s own tuning to produce a really enjoyable tonality overall – this is a great pairing!

Brainwavz R3 (32 ohm): The neutral presentation from the R3 really shows how close to neutral the Pervasion’s sound is. There is definitely a touch of warmth, but the Pervasion sits closer to neutral than I would have thought when listening with the Noble K10s. The R3 + Pervasion combo sounds clean, agile, and beautifully balanced. You can hear that the R3s are holding back the ultimate performance levels of the Pervasion, but it still sounds very good and it’s reassuring to know how much more the Pervasion has to give.

Sennheiser Momentum On Ear (18 ohm): This is a really nice combo with plenty of character through the mids, plenty of space in the stage and a really enjoyably balanced sound overall.

Thinksound On1 (50 ohm): Another combination that sings. Despite the slightly warm approach from the On1s, the combination sounds clean, transparent and very natural – this was a combination I didn’t want to break when it came time to try the next pairing.

Alessandro MS-1i (32 ohm): This is a match made in heaven. Sure, the MS-1s are a relatively budget headphone, but with the great sound presentation from the Pervasion the results are really exceptional – clean, enjoyable, engaging and impressive. I think if you gave this $500 combo to someone in a blind test they’d have a hard time picking it for its price when compared to some of the $1000+ portable setups I’ve heard.

Beyerdynamic DT1350 (80 ohm): The Shozy Alien started to falter a little with the 50 ohm On1s and the 80 ohm DT1350, but the Pervasion just keeps on performing with both of these (slightly) tougher-to-drive cans and continues to sound excellent with just a small increase in the volume level.

Fischer Audio FA-011 LE (160 ohm): While the sound is very good from this combo, I’m not convinced I’m getting the most out of the 160 ohm Fischers, but that’s most likely a result of their mediocre sensitivity (not a knock on this awesome headphone, just a statement of their need for a bit of extra juice). As it is, the Pervasion is still extracting about 90% of the quality I expect from the FA-011 LEs so it’s still excellent.

Audeze LCD 2 (70 ohm): By all rights this is an unfair test, but the Pervasion sounds incredible with the LCD 2s. I have rarely heard them sound so clean and spacious. There may be a slight reduction in bass impact, but it’s subtle and actually allows a greater sense of transparency and clarity – this is a winner for kicking back on the lounge methinks! Even though I can hear that there’s a bit of body missing from the LCD 2s in this setup, the sound is still very enjoyable thanks to the Pervasion’s outstanding baseline sound quality. Just wait till I add an extra amp!

Sennheiser HD800 (300 ohm): Also an unfair challenge in theory, but an eye opening result in reality. The sound from the HD800s proves definitively that the LCD 2s were lacking a bit of bass when driven by the Pervasion, but the HD800s are getting everything they need and they sound fantastic straight from the headphone jack of the Pervasion – that’s impressive!

This exercise showed me two things:

1. The Pervasion has sufficient power to comfortably drive anything except lower efficiency ‘phones. Sticking to lower impedance and / or high sensitivity ‘phones will yield consistently excellent results with the Pervasion
2. The Pervasion sounds great with basically any earphone or headphone, but particularly excels with slightly more neutral ‘phones like the HD800s and Brainwavz R3. The sound is still excellent with warm ‘phones, but the little bit of warmth from the Pervasion makes it a perfect partner for neutral, slightly cool, or any ‘phones with a lift in the upper mids and treble (e.g. Alessandro MS-1)

Line Out

Moving to the line-out lets me add my favourite portable amp, the FiiO E12 DIY (running the OPA627 op amp) and reveals just how incredibly good a well-implemented Wolfson WM8741 can sound.

Many people (myself included) think of the Wolfson DACs as warm and a little smooth, but the line-out from the Pervasion is very neutral (and that’s a compliment). Comparing the Pervasion to the Matrix X-Sabre, the X-Sabre comes out sounding noticeably warmer. Despite the X-Sabre having a slightly more refined sound overall, the Pervasion holds its own with outstanding detail, neutrality and a nicely balanced soundstage that is less intimate than the X-Sabre, but without losing soul and emotion. The >$1000 X-Sabre still wins of course, but when we’re comparing a mains-powered desktop DAC housed in a carved-out solid aluminium shell to a portable, battery-powered audio player, the level of performance from the Pervasion really is extraordinary.

Returning from my desktop rig to the more conventional setup of Pervasion + E12DIY, the beautifully neutral output from the Pervasion lets the E12DIY work its magic and really sing with the K10s. Gone is the slight mid-bass warmth from the Pervasion’s own built-in amplifier and in its place is gorgeous detail in a perfectly smooth and refined package. There’s no harshness or edge, but also without no perceivable roll-off. The sound is spacious, clean, detailed and marvelous. The Pervasion manages to match the excellent detail retrieval of the FiiO X5 with the organic and coherent presentation of the Alien – basically it’s the perfect combination.

Listening to Steal My Kisses from Ben Harper’s Live From Mars album and the separation of different sounds is really excellent. The individual placement and definition created between Ben, the audience and Ben’s human beat box, Rahzel, is extraordinary and creates a real sense of depth. All of a sudden, this pairing couldn’t be any more perfect with the Noble K10s!

Summary

The HUM Pervasion is an interesting device. Some may find the mediocre Wi-Fi and Bluetooth implementation a real issue. Some might think it looks a bit basic in the world of AK120s and AK240s, but those who are interested in it purely as an audio device might find themselves marveling at the sound this little red monster can produce. With neutral ‘phones and those possessing prominent treble the on-board amp is excellent and plenty powerful. For those with external amplifiers, the line out from the Pervasion is top notch and really worth a listen. Add to that the fact that the Android OS provides for endless adjustment and customisation and many will find the HUM Pervasion to be everything they ever need in a DAP. I for one am going to be completely satisfied for quite some time I think – the HUM Pervasion is great!

Don’t forget to check out the update I wrote after sending my Pervasion back to HUM at their request. If you’re thinking it’s sounding promising already, you have to HUM Pervasion Update!