A Survey of Digital Audio Players Part 2 OnePlus One

DAP2_OnePlusOne_Photo_Main

OnePlus One ($299)
I expect most people reading this will recognize the name OnePlus—the upstart phone maker really took advantage of internet marketing tactics since their launch in 2014...although it didn't always go as planned. I assume they felt this type of unorthodox marketing was the only way they could hope to compete with juggernauts like Samsung and Apple. Interestingly, people I meet in "real life" don't usually know anything about the brand. The comment I often get: "Nice phone, what is it?" When I reply "OnePlus One" they stare blankly as if I'm speaking another language. I'm tempted to just make up a seemingly-recognizable name in the interest of saving time. "It's a Samsung Galaxy One Plus." That ought to do it.

While OnePlus has a model Two launching soon (almost certainly released by the time this goes to press), there's always a newer model phone just around the corner. It's almost obnoxious how fast things move these days, where today's flagship phone is tomorrow's discount option. But the original One was the model available when I started this article, and seems to be a perfect representation of a nicer phone that Joe 12-pack might actually own. So it still seems relevant. We could substitute one of the newer Samsung Galaxy S or Note models, or the HTC One M8, or an LG G3, and the results probably wouldn't be all that different. The main point here is to explore the capabilities of a modern smartphone and see how far it trails behind the experience of using a dedicated portable audio player.

External Design
With a 5.5" display, the One is on the larger side for a smartphone. But, being a phone, the form factor is somewhat different than the majority of the field here. The typical shape for a dedicated DAP is more on the thick, stumpy side, while the One is taller and wider but also significantly thinner. Whether this is a good thing remains a matter of opinion. I will say the display here is quite stunning, significantly better than anything else in this roundup including the Calyx M and the Astell&Kern models. Build quality is reasonably solid and the weight is quite manageable compared to the others in the group.

Again, as a smartphone, the One comes at things from a different angle. Thus we get physical buttons in the form of power and volume up/down, and that's it. I sometimes miss having transport buttons available like many of the others do. We do get an external speaker though, which is almost unheard of for a DAP. Not that it sounds great (obviously), or is something you'll be likely to use for any type of serious listening, but it does come in handy every once in a while. Overall I think it's a trade-off—that huge, beautiful display is a plus, while the lack of transport buttons is slightly annoying.

Internal Design
OnePlus has been somewhat obtuse about the audio side of its device. In a Reddit Ask Me Almost Anything, OnePlus co-founder Carl Pei specifically mentions using a Yamaha DAC chip in the One. Yet teardowns show that not to be the case at all—the device actually uses a Qualcomm WCD9320, which is a CODEC also seen in other prominent phones like the Samsung Galaxy Note 3 (US version) and the LG G2/G3. While the name might not bring the same cache as Wolfson or ESS, phones using this Qualcomm solution have generally earned a reputation for above average sound quality. In fact the LG G2 was marketed as something of an audiophile-friendly phone, including native FLAC support and 24-bit/192kHz playback capability. Qualcomm also makes the popular Snapdragon processors favored by higher-end phones. So, whenever you see a Snapdragon 800-series chip on board, you're likely to also get this same audio solution. Of course implementation (on a hardware and software level) is everything—results will vary. The One has an output impedance approximately 2.5 Ohms which is similar to the iPhone 6 as well as the LG G2 and G3. It also supports FLAC, ALAC, and WAV files up to 24-bit/192kHz without any resampling.

Aside from the initial DAC subterfuge, OnePlus is very forthcoming about all their other hardware—after all, they call the device a "flagship killer". I find this to be a refreshing change from the audiophile oriented DAPs which go heavy on audio chip descriptions but very light on the remaining hardware. I'm not quite sure about every little detail for the Astell&Kern or Pono devices, I do know the One packs some nice hardware. As I'll discuss in the "user interface" section, it really does contribute to the overall enjoyment of the device.

The One was available at launch with either 16GB or 64GB of internal storage. With no option to add more via microSD, the 64GB version was the clear choice. While that may still seem a bit low, keep in mind the One can handily access cloud and network storage, where many other DAPs demand old-school file transfers. When I originally planned this article the 16GB One sold for $299 with the 64GB upgrade adding an extra $50. But as I write this OnePlus seems to only carry the 64GB model for a reduced price of $299, probably due to the model Two being the hot new model. The 64GB version of the Two is rumored to go for $389 and doesn't really add anything from an audio perspective, so the original will remain a viable option depending on your focus.

User Interface
The One runs a version of Android Lollipop called CyanogenMod, blissfully free of the bloatware we find on most Samsung devices (among other offenders). Interestingly, Cyanogen and OnePlus have apparently decided to call it quits, so the OnePlus Two will use a different Android build called Oxygen. OnePlus One users can also load Oxygen if they so choose, but it calls for a somewhat complex manual installation and doesn't seem to offer any compelling reason to switch at the moment. Perhaps that will change as Oxygen matures.

The stock playback app is Google Music which I find serviceable but somewhat underwhelming. Thankfully the Android experience is one of rich variety—there are several excellent alternatives available. Neutron, HibyMusic, jetAudio, Pixel Player...the list is fairly extensive and includes both paid and free options. I love having choices that alter the user experience, which is not typically something you'll find in a dedicated DAP. I also can't stress enough how nice it is to have access to subscription services like Tidal and Rdio via their apps. I recommend loading up a few dozen gigabytes of offline audio and skipping the whole "streaming" aspect, though your data plan will dictate your behavior in this regard.

It's hard to go into further detail in this category, as the experience can change from one user to the next based on their app preferences. In this way the One is far ahead of every other device here. Some DAPs allow swapping themes or skins, but nothing except perhaps the (Android based) Sony ZX2 has anything approaching this level of customization. Factor in the potent processor, generous RAM, and Full HD resolution, and there really is no competition in this aspect.

Connectivity
The One again stands out from the DAP crowd due to its alternative focus. As mentioned prior, the non-expandable memory necessitates a choice between 16GB or 64GB worth of onboard storage. Did I mention you should not bother with the 16GB version? I can't see how that would be very useful even for casual listeners, unless they stream everything from Spotify, Rdio, or Tidal and never save anything to storage. Which of course is not very realistic due to data caps and spotty reception in some areas. Besides, with the price difference between models being less than we see in other devices (I'm looking at you, Apple), the higher model is easy to justify.

In any case, the One really only has two physical connection points—the 1/8" headphone output and the micro-USB port. That means no dedicated line-out connection for driving an external amp, and no SPDIF out as most of the competition has in one form or another. All is not lost, however, as that micro-USB slot ends up being really quite handy. Connect most any USB DAC and the One can feed it; sometimes it works with the native Google Music, other times it requires something like the free HibyMusic app. This opens up many options for portable devices like the Resonessence Labs Herus or the numerous other options out there in this category. Or, use it at home with any number of excellent devices. This functionality can be found in other phones as well, though some don't play as well with USB DACs. Remember, I'm using the One as a sort of stand-in for the segment, representing any quality phone and the experience that can be found by using it instead of a dedicated music player.

Another important consideration, one which isn't seen much on dedicated DAPs, is wireless connectivity. Bluetooth is here and it works very well—connect to a car stereo, a table-top speaker system, or some bluetooth headphones. The Astell&Kern players have bluetooth as well but I find it very limited in terms of signal strength, which I'll discuss later. The One is among the best bluetooth sources I've tried, with excellent distances that should accommodate most circumstances. Then there's WiFi, which is handy for file transfer, UPnP streaming, and plenty of other applications. In short, the One does things most DAPs can't, which in many circumstances makes it a better choice.

Battery
This is tough to judge as it really depends on your particular use. If we put the device in airplane mode and thus deactivate many of the power-draining connectivity aspects, it can work as a pure music player for quite a long time. I played CD quality FLAC files for 24 hours straight and still had nearly half my battery life available. Real world usage will vary based on several factors: How often do you have the display on? How loud are you listening? What type of files are you using? FLAC and particularly hi-res FLAC tend to burn through batteries more quickly than mp3, for example. Honestly though, this really isn't the point; I don't think most people want to carry a device like this as a dedicated music player. The goal here is to have a phone, which is already with you at all times anyway, and have it also function as a reasonably nice playback device.

With normal use as a smartphone—some talking, some texting, emails, web browsing, various apps for weather and maps and whatever else—the OnePlus One seems to have reasonably good battery life. It's not spectacular, nor is it below average. The important point is that battery life seems good enough where I can afford to throw in several hours of music playback without worrying about making it through the day. I basically charge every night while I sleep, though realistically I could probably afford to skip a night here and there. But I'm one of those people who like to have 30% or more battery by the end of the day "just in case". What I'm getting at: the OnePlus One has enough battery life to where it doesn't preclude fairly heavy usage as a portable music player. That's not something I can comfortably say about every phone.

Sound Quality
Here it comes, the critical area where I either trash this pretender as being vastly inferior to dedicated units, or praise it as being so competent that spending extra on a fancy DAP makes little sense. As is often the case, the truth lies somewhere in the middle. Right out of the box, using the stock Google Music player and no EQ or other sound tweaks, the OnePlus One is a fairly impressive device. I've owned several recent Android phones which very clearly sounded like crap right from the start. Background hiss even with non-sensitive headphones. Weird bleeps and bloops, static, or other sound glitches. Obvious distortion. Yes, it's 2015 and you'd think even the most basic Android phone would have acceptable sound by now, but for whatever reason that's just not the case. I find that iDevices are consistently satisfying where Android devices CAN be, but often are not. The OnePlus One is an Android device which gets it right, and is thus an enjoyable music player even for discerning listeners.

Listening primarily on the go with my Noble Audio 4C custom in-ear monitors, mainly using CD quality FLAC files, the One doesn't feel completely out of place in this group of higher end dedicated players. It has good balance from top to bottom, and treble detail—often the bane of poorly done playback devices—is rendered cleanly. Imaging is a little imprecise and soundstage isn't the largest, but generally speaking this is a solid result from a non-specialized device. I very much enjoyed it while on the go, with no glaring weaknesses to ruin the fun. I'd call it roughly on the level of a modern iPhone which is a compliment in my opinion... and unlike Apple's devices, the One doesn't force us to jump through hoops just to play FLAC files.

If I find a quiet spot and do some really critical listening, I do note a general lack of transparency compared to the other DAPs here. There's a bit of a "blur" to the presentation, a homogenization where instrument separation isn't up to the same level as the others. And the treble presentation isn't as clear or transparent as the rest of the field. But again, this isn't super obvious during casual listening, which is pretty much what the One is all about anyway. Ever hear a photographer mention that the best camera is the one you have with you? That same concept applies here. Even the best smartphone camera won't replace a full frame DSLR, and neither will the One match a high-end dedicated DAP. But that's not really the point is it? "Good enough" is what we're going for here, and I'd say OnePlus hits that mark.

Earlier this year OnePlus rolled out a system update that, among other things, added something called MaxxAudio. A joint venture with Waves Audio, MaxxAudio is a fairly useful app which adds quality EQ options along with various other sound enhancement features. Plenty of other EQ apps can be had but I applaud OnePlus for having this option built in as it actually works fairly well. The presets seem less heavy handed than I've seen in other EQ apps. The layout is very clean and usable. And the 10 band EQ is quite easy to work with thanks to that large, responsive screen. Many DAPs have some type of EQ on board, but adjustments are rarely this easy. My only real complaint is that it doesn't always work depending on your playback choices. The default Google Music app is compatible, as is Spotify, but Tidal remains unaffected. So it requires trial and error to see if your favorite players can make use of this option.

There are some obvious limitations involved in an all-purpose device like this. The biggest issue, though not really a surprise, is a lack of juice. Using IEMs and sensitive portable headphones is generally fine, but anything beyond that is where the limitations start to become more obvious. I had good results with the HiFiMAN RE400, various custom IEMs, and the RHA MA750. I also enjoyed the Sennheiser Momentum and V-Moda XS. These are the types of headphones that mate perfectly with a quality smartphone like the One. Switching to something like an AKG K7XX or a Sennheiser HD650 will prove disappointing, not to mention any of the more difficult to drive planar magnetic options on the market. I don't really consider this a huge drawback though—the One is obviously a portable device, and those headphones just fall outside its scope. This is where you might pick up a nice portable DAC/amp unit to make up for those imitations.

I do have to mention the output impedance of 2.5 Ohms as being somewhat problematic. Certain IEMs using multiple balanced-armature drivers sound "off" in places, due to impedance related interactions. The difference in some of these IEMs might not be immediately noticeable but if you happen to use something like a Shure SE846 or AKG K3003 it should be fairly obvious. I'm willing to go a little easy on OnePlus here as several of the more expensive dedicated DAPs have similar output impedance, and the One is an all-purpose smartphone rather than a focused music playing device. Still, something to watch out for when choosing IEMs.

Ultimately the OnePlus One will satisfy, or not, based on expectations. If you keep a proper perspective and don't think of it in terms of expensive dedicated players, you should find yourself enjoying it for what it is: a competent, do-it-all smartphone with solid audio quality. Nobody expects it to keep up with an AK240 or even a Sony A17. What it does do is something iPhone users have taken for granted for a while now, something that's been a bit lacking on the Android side of things. Fortunately, if OnePlus, Samsung, and LG continue this trajectory, that discrepancy will keep getting smaller.

COMMENTS
Alexander Portnoy's picture

Great work, John.
This project will make a good basis upon which to judge the imminent release of Pioneer XDP-100R and the Geek Waves.

John Grandberg's picture
And yes, I suppose I could go on and on... I suspect next year will bring half a dozen (or more) significant releases. We'll see what happens and what I have time for.
ManiaC's picture

Questyle QP1R vs Luxury & Precision L5 Pro

John Grandberg's picture
the Questyle QP1R here and it's pretty great, certainly in the running for Wall of Fame. I tried the original L5 and it was terrible in build and UI, but the L5 Pro is all different so who knows.
Imusicman's picture

HiJohn, Ive read part 1 and part 2 with great interest and eagerly await part 3. Great review and exactly on point with this growing category. I have narrowed my choice for DAP down to the Questyle QP1R and Cayin N6 after discounting the Acoustic Research ARM2. Having spent time with both which would you recommend? Not sure if this swings it one way or the other but I have the opportunity to buy a demo N6 at £270

John Grandberg's picture
because I like them both. N6 has a significantly more powerful amp stage if you intend to use it with difficult full size cans. Some people might like its up/down/left/right control scheme better too. The Questyle can accommodate a far bigger library thanks to dual microSD slots. It also has slightly better battery life, is smaller, and has a more brilliant, detailed presentation - which may or may not be a good thing depending on your preferences. I'll go more into this in part 3 though.
Imusicman's picture

Thanks for getting back to me John. Much appreciated. There's definitely pros and cons to each player depending on what's important to the individual consumer. I have taken the plunge and ordered the QP1R which hopefully should be with me next week :-) Lets hope my leap of faith is rewarded as I haven't been able to find anyone local who is stocking it to give it a demo which is not ideal.

John Grandberg's picture
I'm listening to it right now, sounding quite nice with a 24/96 version of Paquito D'Rivera's Portraits of Cuba and the Noble Audio K10. It's not perfect - I'll get into the minor frustrations which you will no doubt notice on your own. But nothing I consider a dealbreaker. I do wish Questyle has better distribution though....
Imusicman's picture

Being a newbie to this hobby I am in the very early stages of my journey to find the holy grail of sonic perfection. I am starting from a relatively low base with my iPhone 5 so I am hopeful of larger gains initially but do expect less as my hardware base level improves and the differences become more subtle. If the QP1R fails to impress I will be looking to test out my suppliers returns policy or failing that stick it on eBay. Given the supply/demand situation I can see it selling PDQ so no drama either way.

silverarrows5's picture

Hi John,

How about the Marshall London Smartphone?

John Grandberg's picture
I'm just not sold on that one as being anything other than a lowish-spec phone with minor customization. I'd stick with the OnePlus or another more established phone if you don't want a dedicated DAP.
tony's picture

Well, this is just plain Brilliant. It's certainly the next thing I'll be concentrating on, I have a very good Main System and a equally useful Wireless Headphone System.

I travel extensively and would love a capable & portable "Source" device. I've seen your JA wandering around using an AK240 (I think) to carry his music to "Field" evaluate gear. I thought and still think his little device would give a useful result ( at least for my purposes and probably the vast World of Music lovers ).
A small LapTop is far to big but more affordable. How can a person get a Laptop's functionality in a portable ( shirt pocket ) package and how could a little device function properly with only a tiny screen? Plus, is there a little player offered by a supportive manufacturer?
So, it seems, you are working to reveal these things.

Philosophically, I think we music lovers strive to build our own "Music Hall Venues" to play the music we buy, own and enjoy!
These tiny Players take our personal Venue down to miniature sizes.

If JA's little AK240 is anything to go by, we are about to have our entire HighEnd music system in the "Palm of our Hands" ( except for our Box Speakers, of course ).
Now, if we can organize our music into little SD Memory Cards we might be able to have a Wallet with our entire collections.
This "Pipe Dream" has always seemed so "Distant Futuristic" in concept and nature but you seem to be revealing that it exists now.
I'm all Ears!
I'll be reading every word you have to say on this matter.

Tony in Michigan

ps. Thank You

Rillion's picture

Hi John,

It is great that you are doing this! Reviews like these of DAPs are to find. Even reviews of smartphones generally have very little intelligent commentary on sound quality if they mention it at all.

On the models that have so-so battery life, it would be nice if you could mention whether or not the device can continue running noise-free while charging. I have a 5V Anker battery pack that can add significant extra power.

John Grandberg's picture
I'll certainly check on this moving forward. I can confirm that the Consonance Suzanne works fine while charging in the dock, as do the AK devices, and also the Cayin. Obviously the OnePlus will (same as any phone) but I'll have to try it to confirm it doesn't add any detrimental noise or other issues. The only one I'm unsure about is the Pono so I'll give that a shot and report back.
Rillion's picture

Cool! Thanks!

echineko's picture

I was hoping to see it included, after you hinted it might be in Part 1. There's always part 3 I suppose, would be interesting to see it compared against the AK 240/380 as well :)

John Grandberg's picture
Sony took a while to send it my way, so I didn't have enough time to spend with it compared to these others. ZX2 is definitely in for part 3 though.
zeissiez's picture

Hi John,

I'm an expat based in China, over here I got the chance to audition various Chinese DAPs. To my surprise, many of them are actually very good sounding, and some of them more so than the A&K in sonic performance. I have heard the Cayin N6, Consonance, ibasso dx90, hm-901, Questyle QP1R, Lotoo Paw, Fiio X5 and many more. One brand that stood out is Luxury & Precision. Their L5, LP5 silver and gold edition are the best DAP I heard regardless of price. The entry level model L5 for example is clearly better than the N6 in sonic performance. Now the latest model L5 pro is said to be a much improved model over the previous 3 models. So I think it's good to include it in your reviews.

John Grandberg's picture

Thanks for the perspective. I've only had a chance to mess with the original L5 and it seemed like a prototype (it was a production model though) - poor build, terrible UI, only decent sound. I'll have to see if I can get my hands on the new stuff as it certainly does look improved.

I agree that Chinese DAPs can sound excellent. The HiFi ET MA9 was one of my favorites on sound, but less so on reliability, battery, and UI. Reliability is a big one for me.

whyeme's picture

Please please review the xduoo x3 when you do part 3. It uses the CS4398 DAC chip and Texas Instruments amp chips and sells for only USD110 inclusive of free shipping. Perhaps it could be a budget DAP shootout to get more youth into this hobby.

Cheers!

Bennyboy's picture

It's not a question of age, but of income. Not all of us are loaded enough to drop a grand here there and everywhere on this stuff.

John Grandberg's picture

That makes sense. However - a company saying "we want to appeal to a younger demographic" is a lot more PC than "We want to appeal to poor people" or "people with less disposable info". So you'll almost always see it framed as a "youth" thing.

But I agree, some of these are steep, and I'm glad there are some good options to be had for lower prices.

Bennyboy's picture

Some of these new 'high end' players are just daylight robbery.

I recently bought the Fiio X1 - cost me 95 quid and sounds ACE.

ashutoshp's picture

Thank you for your efforts in scaling the growing landscape of media players. TBH, I have little interest in media players myself mostly from a convenience perspective. But your smartphone inclusion got my curiosity.
Do you think the audio limitations apparently inherent in the smartphone are a DAC or an amp issue? In other words, the DAC is fine but the amount of power it can output is the major limiting factor. The reason I ask is because the choices in amps or amps+DACs are similarly vast and I am confused as to what would work best, an amplifier via the headphone out, or a DAC+amp via USB OTG/Lightning CCK?
Moreover, it seems that (cheaper) DAC+amp 2-in-1s usually trade-off DAC quality for amplifier capacity or vice-versa. If the smartphone DAC is fine then I can go for a high quality headphone amp rather than stick with a compromise, which I feel I'm currently making anyways with a smartphone/tablet. FYI, I only listening to streamed music from TiDAL on an LG G3 and iPad Air. Thanks in advance.

detlev24's picture

IMO there is no definite answer to your question since it depends very much, on which headphones you use. Generally, I would say the amplification circuit around the DAC is the bottleneck of most devices.

Since your question is directed to John, it might be useful for him to know the type(s) of headphones you use and the budget you plan to spend on such a device, since (audible) trade-offs do not necessarily need to be made.

Best regards

John Grandberg's picture

I basically see the amp section of a phone as being the weakest link - on a better phone, the DAC is pretty decent. Not as good as the better dedicated DAPs but good enough to be enjoyable nonetheless. The amp portion, though, is limited in terms of drive (and often output impedance as well) so it becomes the biggest issue.

Having said that, the market seems to focus more towards combo units. So I might go that route anyway. I've had more luck finding good combo units than straight amp-only portables.

The upgrade path will depend on what headphones are being used, as well as your intentions for portability. If "on the go" listening is a must then something small like the Resonessence Labs Herus should do the trick. I also really like the Oppo HA-2. If home use is the goal, you could go for a desktop setup, which then opens things up a little more for separate components.

ashutoshp's picture

I have the Hifiman HE-400i (home use), Sony's XBA-H1 and Ety's HF3 (outside use). Of these, the Etys don't seem to scale with more power but the other two definitely do. the Hifimans are actually too much for the phone, but not for the iPad even though they seem to get limited sometimes.
I was looking at a portable set up not only because of my need for mobility but I can then use it for bedtime listening with the Hifimans. My budget is $300 . I like a fast, clear, hard-hitting sound. But I hate boomy bass or tizzy treble (eg, DT880....ouch). The Sony XBA-H1s are quite boomy in the bass when played through the HP out of my phone but not at home with my desktop DAC/amp set up. The XBA-H1 is also why I started researching amps or amps/DACs like the HA-2 or Alo's new Rx (amp only I think).

detlev24's picture

You can try the two FiiO E12 amplifiers and see, if they suite your needs.

I have listened to the E12 on a HIFIMAN HE-500 (which needs more power than your HE-400i) and for such a small package, it sounded good at my listening levels and with the types of music, I listen (classical music, included). I switched "BASS: ON" but I did not use GAIN, since this made noise audible (you may not find it disturbing during playback, depending on the music genre) and with CROSSFEED, clarity suffered (the latter is useless, anyway - unless thoroughly matched to your headphones and music).

On the other hand, I do not recommend the E12 with IEM, since I had noise using UE TripleFi 10 but for a technical aspect, that was no surprise. For IEM, try the optimized E12A!

I think the HE-400i may sound great using an E12 and for IEM, the E12A could just do it.

detlev24's picture

If considering FiiO, also try the E12A on the HE-400i. Might need "GAIN: H" but depending on your taste, you could like it more.

An there is also a E12DIY around (with swappable op-amps, for different sound signatures), as alternative to the E12.^^

Long time listener's picture

I too would like to see a review of the two players above.

Also, just how well do these players compare to separates? For example, an iPod feeding an Algorhythm solo -R plus a Vorzuge Pure II amp? Do they come pretty close? Thanks

John Grandberg's picture

Both are to be included in part 3.

I personally think the better DAPs give up very little compared to separates. Obviously depends on the models in question... but the small improvement brought from lugging a big stack is typically not worth it (for me) compared to a quality DAP.

I might feel differently if I used the stack for home use with occasional portable listening. With big, difficult to drive cans, the dedicated amp could make a more significant difference.

zobel's picture

Been awhile since he has written anything. Thought he might offer a wrap-up on the last project. Hope he is feeling good.

Tyll Hertsens's picture
Went to RMAF, I'll be posting the Big Sound 2015 wrap posts this week.
Broman's picture

I played with a OnePlusOne and thought it unexceptional compared to HTC One 9. The new phone I want to try is the LG V10 with ESS DAC. Thank you for including a phone in this survey. I go for long walks in cities and the less I carry the better.

John Grandberg's picture
I like the OnePlus One slightly better than the HTC One M8. Not sure about the latest HTC though. I already have an email in the LG about the V10, I've been keeping an eye on that since I first saw the ESS DAC (and headphone driver) being used. Not sure many big phone companies are actually willing to participate though, we'll see.
elfary's picture

If one take a look at gsmarena frequency plot of the OnePlusOne one can discern that output impedance it's headed to the 10 ohms range. (They measure with AKG headphones that have an impedance bump at the 50Hz).

Hence i was wondering what headphones have you used. I don't think balanced armatures earphones can play as nice on the OnePlus as they play on HTC, Apple or Samsung flagships.

In any case is nice to see smartphones tossed in since their ergonomy is killer.

Just my 0.02

John Grandberg's picture

I use a matched pair of resistors soldered to a Neutrik jack, rather than a headphone as dummy load. I'm fairly certain that my results are accurate for my particular OnePlus One. Can't speak for any silent revisions or manufacturing variability that could explain a different result, nor can I say GSM Arena didn't make some mistake somewhere. In my case I do enjoy IEMs with the OPO, with certain limitations of course. My UM Merlins (which drop into the single digit ohm range at some frequencies) are not a good match, but many other IEMs are.

It makes sense that performance would be on par with the top LG and Samsung models, as they tend to use very similar hardware.

I will say the HTC flagships seem to have the advantage driving full size headphones. More output voltage, more drive, more authority. I personally don't have much use for that but some people might.

elfary's picture

If i have to trust your measurements or gsmarena ones i'll go with yours i heartbeat. In gsmarena they so 't know very well what they are doing. An i know that on certain smartphones z changes from region to region (m8 had 9 ohms in the China market. In Europe it has just 1.

veggieboy2001's picture

This is a really comprehensive survey of DAPs...I'm looking forward to part 3. I'm currently researching a replacement for my Fiio X3 (1st gen) so this is timely indeed! Have you had any experience with Shanling? I've read some good things about both the M2 & M3 and I was hoping they were on your radar...there are so many people getting into the DAP game these days it's hard to keep up. Thanks for taking on this task...I'm excited to hear your final results!

Ranstedt's picture

Any idea when part 3 will be available?

I'm about to get my first great pair of headphones and would like a nice, not very expensive, DAP that has a very good price:quality ratio.

Thanks.

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