The Best Portable Headphone Amp With Built-In DAC

AudioQuest DragonFly Red

Best for computers

Portable and powerful enough to drive high-impedance headphones, the DragonFly Red works with laptops and mobile devices, but drains the battery.

$200 from Amazon

$200 from B&H

The AudioQuest DragonFly Red is our pick for laptop use. It’s very portable and simple to set up and use, and it sounds great with nearly all the headphones most people use regularly (technically speaking, those with 250 ohms or less impedance). The DragonFly Red is about the size of a standard USB thumb drive, so it will pop right into your laptop bag or pocket without adding much bulk. While it is plug-and-play with Windows 10 and Mac computers, you should still download software to your PC or Mac to get the newest firmware updates. Your machine will recognize the DragonFly Red immediately when you plug it in and give you the option of selecting it as your audio-output device.

Our expert panelists all loved the sound quality of the DragonFly Red. As we stated before, it offers a very slight improvement over what you’d get from the headphone jack of a typical phone or computer. Our listening notes for the DragonFly Red consistently describe a little extra detail on the highs, a tad extra spaciousness and separation to the sonic depth of field, and a bit more precision in the handling of bass frequencies. While the DragonFly Red probably won’t make your headphones sound massively better than you are accustomed to, it definitely won’t make them sound worse.

The DragonFly Red handles higher-impedance headphones really well. In our measurements, it could deliver a max output of 16 milliwatts in headphones with impedances ranging from 32 to 250 ohms. For most listeners, using most headphones, an output of 15 mW or greater is more than enough power for listening at a sufficiently loud volume level.

Like our other picks, the DragonFly Red has a low output impedance (we measured 3.1 ohms), which means it should produce consistent results even with headphones that have a large impedance swing. Our panelists experienced that effect firsthand when listening to the Shure SE535: Those headphones’ big impedance dip (PDF) makes them vulnerable to coloration, but the DragonFly Red drove them smoothly and clearly.

AudioQuest has a good reputation in the audiophile community, and it backs up the build of the DragonFly Red with a one-year warranty. The company is invested in adapting to the changing digital music environment, and it releases software updates to keep its models current (for example, this MQA firmware upgrade), so you’ll be less likely to need to buy a new device—or wait for an update to resolve issues—than if you owned a cheaper alternative.

Our pick: Flaws but not dealbreakers

The DragonFly Red has a few downsides. Although it functions with mobile devices, you’ll need to buy an appropriate adapter for your portable player, and that can add up quickly. iPhone/iPad owners will be out around $40 for Apple’s Camera Adapter. Android owners will need this AudioQuest USB–to–Micro-USB adapter. And folks who have only USB-C ports on their laptop will need to snag one of our adapter picks from Aukey or Anker. On top of that, the DragonFly Red’s additional power draw is likely to cause your mobile device to lose battery life much more quickly than usual. So while using the DragonFly Red with a mobile device is completely possible, we don’t recommend it unless you are near a power source.

If you have very high-impedance headphones (600 ohms or more), the DragonFly Red likely won’t be able to give you the volume you crave. Brent wanted to see a maximum usable output of at least 10 mW, and the DragonFly Red didn’t quite get there when faced with a 600-ohm pair of cans (we got 7.2 mW). That said, not a lot of people have really high-impedance headphones that they travel with, and even fewer of them will want a DAC/amp under $400.

On the flip side, the DragonFly Red can be cranked too loud with 32-ohm headphones, while our other picks still sound clean even running full blast. At max volume into 32 ohms, our THD+N (total harmonic distortion plus noise) measurement was 22.127 percent. That said, if you turn it down about two notches, the distortion drops to almost nothing (0.025 percent), and the listening level is still plenty loud.

And lastly, the DragonFly Red has only a ⅛-inch headphone jack, so if your headphones have a ¼-inch plug, you’ll need yet another adapter. However, this is pretty standard for DAC/amps at this level, so it wasn’t in any way a dealbreaker for us.

Our pick for mobile: Oppo HA-2SE

Oppo HA-2SE

Best for mobile devices

This battery-powered Oppo model has more inputs and won’t drain your battery, but it’s as big as an iPhone.

Buy from Amazon

*At the time of publishing, the price was $300.

Our pick for mobile devices, the Oppo HA-2SE is not only self-powering but also one of the most intuitive, plug-and-play DAC/amps we tested. Unfortunately, the company is phasing out production—but if you can find the HA-2SE in stock, we still recommend it. This Oppo model ships with all the cables you need to get right to listening on your Android device or iPhone, so you won’t need to purchase additional adapters to connect it to your music source. If you have a PC, you may need to install a driver to your laptop or desktop, but once you do, you’ll have no trouble connecting quickly. The Oppo HA-2SE can handle pretty much any set of headphones you might try with it, deftly driving 35-ohm to 600-ohm headphones with no distortion and plenty of power.

While the Oppo HA-2SE is larger than our laptop pick, it isn’t massive. About the same size as a standard iPhone, the HA-2SE can sit strapped to your mobile device with the included silicone bands, and it fits into a standard men’s jeans pocket. The size is due to the rechargeable internal battery, which powers the amp without drawing juice from your music player—key for anyone who wants to listen on the go. Plus, the HA-2SE can function as an external battery charger for your phone. This Oppo model’s battery is 3,000 mAH and will last seven hours when you use the device as a DAC and amp or 13 hours as an amp only via the analog line-in. And the HA-2SE charges quickly, reaching 70 percent capacity in 30 minutes and 100 percent in 90 minutes.

In our tests, the HA-2SE was a consistent panelist favorite, producing a minute increase in clarity for high frequencies while ever so slightly refining the lows. When it was powering the Sony MDR-7506, we heard a tiny bit more depth compared with plugging those headphones directly into a phone or laptop. Appealingly, it added no coloration to the HiFiMan HE-1000 V2. But if you do prefer an extra bass boost, the HA-2SE has a Bass+ switch that significantly raises the bass between 20 Hz and 500 Hz. It bears repeating, however, that all these improvements were only slightly perceptible to our trained ears.

Though Oppo recommends using the HA-2SE only with headphones up to 300 ohms, a high-gain switch on the HA-2SE enabled it to drive 600-ohm headphones with 12.4 mW output in our testing, which means you will get lots of volume with all but the highest-impedance headphones (most of which are antiques now anyway). And with the low, 1-ohm output impedance that we got in our measurements, even the most finicky of balanced armature drivers should sound consistent.

The HA-2SE has a luxe executive look and sturdy build quality. Fans of analog dials will love the smooth feel of the graduated volume knob. Oppo has a stellar reputation in the audio world, and the company claims it will continue to back the HA-2SE’s one-year warranty even after it stops manufacturing later in 2018.

Our mobile pick: Flaws but not dealbreakers

Oppo is winding down its US operation, which means that replacement parts may be difficult to come by in the future. Oppo told us it would continue to provide limited customer support and occasional firmware updates for the indefinite future. That’s reassuring if you already own the HA-2SE, but something that should give you pause if you’re shopping.

On the technical side, our other big complaint about the HA-2SE is its inability to decode MQA audio files. According to our contact at Oppo, the company can’t add this functionality to the HA-2SE via firmware in the future. Because MQA is proprietary, this flaw will likely affect only Tidal users who want to stream hi-res audio. The HA-2SE can still play hi-res Tidal music files, but it does so at a lower 24-bit, 96 kHz sampling rate (which is still higher than CD quality). The HA-2SE has the capability to decode other forms of hi-res audio (we used a few such recordings in our tests), but you will need to purchase your music from a source that doesn’t encode in MQA. That said, questions remain about the format, and the benefits of MQA are still being debated.

Like most DAC/amps in this range, the HA-2SE has only a ⅛-inch headphone jack, so you’ll need an adapter for your ¼-inch headphones. Ideally, we’d also prefer a smaller DAC/amp, but none of the more diminutive options can drive headphones without significantly affecting the battery life of your mobile device.

Budget pick: FiiO K1

FiiO K1

An inexpensive option

It isn’t as versatile as our top picks and doesn’t work with phones, but it’s cheap and doesn’t sound that different. It’s perfect for replacing a laptop’s broken headphone jack.

$40 from Amazon

The FiiO K1 is exceptionally small and lightweight, weighing 11.3 grams, less than most USB thumb drives. While the K1 doesn’t sound much better than the average laptop headphone jack, it also doesn’t sound much different from our top picks, and it doesn’t distort, even at max volume. And at 0.9 ohm, it had the lowest measured output impedance of all our picks, so it should sound consistent across its entire volume range. Plus, the K1 is literally plug-and-play, requiring no drivers for Windows PCs or Apple computers. However, it doesn’t work with mobile devices and isn’t quite powerful enough for finicky headphones. But if you have an atrocious sound card or a broken headphone jack and want to spend the least cash possible, the K1 is a great option.

Sound-wise, the FiiO K1 didn’t stand out in our blind-listening tests, which is a good thing. Differentiating between the K1 and our panelists’ favorite DAC/amps was difficult—it was such a small difference, we considered it negligible. The K1 lacked a bit of the separation and clarity of our picks, with perhaps a little less sparkle on the high frequencies, and a little less definition in the lows. But it was a very minor difference overall, and one that many people may not even notice.

However, the FiiO K1 does have some significant limitations. It can’t adequately drive headphones over about 100 ohms (such as the Beyerdynamic DT-880 600-ohm model), and it isn’t compatible with mobile devices. The K1 also can’t decode audio files over 24 bits/96 kHz, so audiophiles who are looking to hear the minute differences in music with higher sampling rates should choose one of our other picks.

How our picks compare

Sound quality

To better understand how close these DAC/amps were in frequency response, Brent played white noise through the AudioQuest DragonFly Red, the Oppo HA-2SE, and the Fiio K1, and viewed the results on his CLIO 10 FW analyzer. (He considers this test a crude one, but it’s the best he could do given the difficulty of measuring USB DACs with his current lab gear.) We also ran the HA-2SE with its bass-boost switch activated. Even considering the relative imprecision of the tests we did with white noise, with the exception of the Oppo’s Bass+ mode, the results were extremely similar, with much less than 1 dB of difference between them. That’s a very narrow margin. If you want to hear what a 1 dB increase or decrease sounds like, try taking this blind test.

Portability

1. Tie: FiiO K1, AudioQuest DragonFly Red

2. Oppo HA-2SE

The K1 and DragonFly Red both resemble a USB thumb drive and are a fraction of the size of the HA-2SE, which is shaped like a standard iPhone and weighs 175 grams.

Features and compatibility

1. Tie: Oppo HA-2SE (works out of the box with iOS, Mac, PC, and Android; no MQA decoding), AudioQuest DragonFly Red (works with PC and Mac; requires separate adapters for iOS and Android portable devices; can decode MQA)

2. FiiO K1 (PC and Mac only; no MQA decoding)

While both the HA-2SE and the DragonFly Red work with most laptops and mobile devices, the DragonFly Red’s adapters are separate purchases and will drain your music player’s battery. However, the DragonFly Red can decode MQA, and the HA-2SE cannot.

Output power

1. Oppo HA-2SE: up to 600-ohm headphones (according to our tests; Oppo recommends 300 ohms or less)

2. AudioQuest DragonFly Red: up to 400-ohm headphones

3. FiiO K1: up to 100-ohm headphones

In our tests, we measured the HA-2SE’s high-gain setting at 12.4 mW of power at 600 ohms. That means, of our picks, it can supply the most power, making it the best choice for harder-to-drive headphones. We measured the DragonFly Red at 16.1 mW at 250 ohms but 7.2 mW at 600 ohms, which means it likely won’t make high-impedance headphones loud enough for most listeners. While the K1 had 41.1 mW at 32 ohms, with a 250-ohm load it dropped to 5.2 mW, far quieter than most people will like.

By the way, most headphones are rated to deliver somewhere around 100 dB from a 1 mW signal, which is pretty loud. For reference, OSHA’s guidelines for laboratory workers (PDF) limit exposure to two hours at 100 dB. And that’s just to prevent “debilitating hearing loss.” You can read our thoughts on safe listening in our guide to kids headphones. For every doubling of milliwatts, you get 3 dB more output, so with a set of headphones rated to deliver 100 dB at 1 mW, you’ll get 103 dB from 2 mW, 106 dB from 4 mW, and so on.

The competition

With a few exceptions, all of these DAC/amp combos sound really similar, so if you are concerned about audio quality, most any of these models will work just fine. What differentiates them is the combination of features, ease of use, and price. But really, excluding a few duds, if you prefer any of these designs over our picks, and you need a DAC/amp, that’s fine—they sound pretty much the same.

If you can find a good price and the device meets your needs, any of the following four models would be a safe buy:

Apogee Groove: During our blind tests, the Groove sounded a bit softer in the mids and a tad more coarse in the highs, but still quite good. It offers a lightweight, easy-to-use design plus its own digital volume control. The Groove works with Mac and PC as well as with iOS and Android, but it drains power from mobile devices.

AudioQuest DragonFly Black: The sound of the DragonFly Black was nearly identical to that of the DragonFly Red—which is to say, great. We heard lots of detail and sparkle on the highs, agile lows, and even, spacious sound in the mids. But the DragonFly Black has a medium output level (1.2 volts), so it’s less able to grow with your headphone collection.

FiiO Q1 Mark II: Landing in the middle of the pack, the Q1 Mark II sounded perfectly acceptable to us. It had a little too much low end that made male vocals sound slightly recessed, and it didn’t quite have the sparkle and life in the highs that our top picks exhibited—when we really paid attention and scrutinized the sound.

Sony PHA-1A: The sound quality on the PHA-1A consistently ranked near the top of our lists, but it was ever so slightly more 2D sounding than our top picks, with a bit of midrange coloration. Ultimately, it was the PHA-1A’s larger, heavier build and shorter battery life that nudged this model out of the winner’s circle.

We also encountered a few DAC/amps that our panelists didn’t like, and we recommend skipping them, even if they’re available at a discount:

Creative Sound Blaster E5: This model consistently ended up toward the bottom of our panel’s blind-test rankings. While the overall sound wasn’t objectionable, our panelists liked most everything else we heard better. Brent described the sound as “somewhat dull, crude, and edgy when compared to the others,” and John and Lauren agreed. Lauren also found it to have lower-end bloat and a more 2D sound quality than most of the other DACs.

FiiO i1: Since the i1 was made for Lightning iOS devices, our panel blind-tested this model against Apple devices. Surprisingly, the MacBook Pro and iPad Mini, through their built-in headphone jacks, and the iPhone 7, through the included headphone dongle, sounded nearly identical with the volume matched. We were able to hear a distinct difference between the i1 and the Apple devices, but our panel felt it was a lateral move: The i1 definitely sounded flatter, both in the frequency-response sense and in the spatial sense. The Apple devices were slightly more boosted in the lows and highs, but that made them sound more 3D. We all agreed that the i1 changed the sound, but we didn’t think that change improved the sound.

JDS Labs C5D: The C5D truly surprised—and disappointed—our panel. JDS has a fantastic reputation, but the C5D was noticeably muddier, bassier, blurrier, boomier, and noisier than any of the other DAC/amps we tested, even though we tested it with its tone switch set to the neutral position. It’s the only model that our blind panel singled out as actively disliking.

What to look forward to

iFi Audio announced the Nano iDSD BL, a $200 battery-powered portable DAC/amp with a 10-hour use time per charge and a claimed output of greater than 3.5 V at a 600-ohm load (20 mW/600 ohm). It’s MQA certified, and it supports PCM up to 32/384 kHz. We will test it when it’s available, but it is a bit large to be considered truly portable.