Up to 84% in savings when you subscribe to The Absolute Sound
Logo Close Icon

Begin typing your search above and press return to search. Press Esc to cancel.

Three Miniature Portable USB DACs

Three Miniature Portable USB DACs

For audiophiles who travel a portable DAC has become one of those “must-have” travel accessories, right up there with a toothbrush and an unexpired credit card. The first generation of portable USB DACs was big and had limited high-resolution capabilities in comparison to the current crop. But as technology marches forward, more capabilities and smaller footprints abound. I’ll look at three small USB DACs in this review—Cambridge Audio’s DacMagic XS, the Hegel Super, and the Resonessence Labs Herus.

Cambridge Audio DacMagic XS
About the size of a small box of wooden matches, the Cambridge DacMagic XS is one of the smallest and lightest portable DACs I’ve seen. It measures approximately 2 1/8″ by 1 1/8″ by 3/8″ and weighs under 4 ounces. On one end you’ll find a micro-USB input and on the other end a 3.5mm stereo output. The top of the DacMagic XS has its own analog volume control, which “fully bypasses the soundcard and volume control of your computer.” The two large buttons, plus and minus, are easy to locate and use even in dark or cramped spaces. Instead of plastic, the DacMagic XS is housed in a beveled brushed-aluminum case that should be capable of surviving a high level of abuse. The DacMagic XS has a small LED next to the headphone jack that glows purple or blue when the unit is operating properly and red when you try to boost the volume past its maximum level.

Inside the Cambridge Audio DacMagic XS you’ll find an ESS 9023 24-bit DAC chip that supports PCM bit-rates up to 192/24 from a USB 2.0 input. Straight out of the box the DacMagic XS is set up as a USB 1.0 device, which will only support a maximum bit rate of 96/24. Switching over to USB 2.0 requires holding down both the + and – buttons for at least five seconds until the small light in the DacMagic XS flashes three times. Once in class 2.0 the DacMagic XS will remain a 2.0 device unless you switch it back.


Three Miniature Portable USB DACs

The most difficult part of using the DacMagic XS with a Mac computer is finding the right kind of connector to attach it to the Mac. The DacMagic comes with a six-inch cable, but if you need a longer one, which I suspect many prospective owners will, the DacMagic XS shares the same type of micro-USB connection as the Astell&Kern AK100, AK120, and AK240. A&K (and others) sell micro-USB cables on its site.

After attaching the DacMagic XS to one of my Macs (I tried it with a MacPro desktop, MacPro portable, and a Mac Mini), the AMSCP (Audio Midi Setup Control Panel) on each Mac recognized the DacMagic XS immediately. Once the DacMagic XS was set for USB 2.0 operation the AMSCP showed that it was capable of handling up to 192/24 files.

The only ergonomic quirk I experienced while using the DacMagic XS was that it was sensitive to static electrical shocks. All it took was a couple of strides across my office and back, then touching the DacMagic to generate enough of a static shock to disconnect the DacMagic from the USB buss—it would vanish from the list of DAC options in AMSCP. To correct the problem I needed to disconnect and reconnect the DacMagic XS from its USB connection, at which point it reappeared on the AMSCP DAC list and began playing as if nothing had happened.

DacMagic XS’s Sonic Sorcery
I’ve seen the question posed on multiple locations on the Web, “Are thumb-drive-sized DACs a real sonic upgrade or merely convenience devices for accessing higher-definition music files?” In the case of the DacMagic XS the answer is clearly, “Both.”

Since most prospective purchasers will want to use the DacMagic XS with headphones, I used a wide variety of different headphones and in-ear monitors with the DacMagic XS. With the most sensitive in-ears, such as the Westone ES-5 custom in-ear monitors (115dB sensitivity), the DacMagic XS did generate some low-level hiss and background noise. With somewhat less sensitive in-ears, such as the Ultimate Ears In-Ear Reference Monitors, the DacMagic XS was quiet enough that the music came from a virtually silent background.


Three Miniature Portable USB DACs

The DacMagic XS’s headphone amplifier section had adequate gain and power to drive the Audeze LCD-2 and Mr. Speakers Alpha Dog headphones to satisfying volume levels with good bass extension. I was quite impressed by the combination of the DacMagic XS and the Grado RS-1 headphones, which can be quirky with portable gear. The bass sounded especially potent in this combination. I also enjoyed the venerable AKG K701 headphones connected to the DacMagic XS. While offering more of a left-brained rendition of music than that of the Grados, the AKGs connected to the DacMagic had well-controlled upper frequencies that still had air and extension.

When connected to my desktop computer-audio system the DacMagic XS did a fine job of creating a believable three-dimensional soundstage that had all the weight, size, and imaging specificity of a “full-sized” DAC. When set to maximum output the DacMagic XS had enough gain to allow it be used like a fixed-output DAC into an analog preamp. While not quite as transparent and revealing as my reference DACs, including the April Music Eximus DP-1 or the latest version of the Wyred4Sound DAC2 DSD SE, the DacMagic did pass enough musical information to be completely involving. I never felt during my time with the DacMagic that it was limiting fidelity to the point of “grayness,” which is the way some “entry-level” portable DACs sound.

 

Although it doesn’t handle every audio format, and isn’t DSD-capable, the DacMagic XS delivers a lot of functionality and sonic goodness for under $200. For audiophiles looking for a road-warrior-worthy portable DAC that will be at home hooked up to any computer, portable or desktop, and successfully drive most headphones, the Cambridge Audio DacMagic XS DAC is a savvy and very affordable option.

Hegel Super DAC
Hegel gave audio journalists a sneak peak at the Super portable DAC during the 2013 Rocky Mountain Audio Fest. I was immediately impressed by the Super’s solidity, both physically and sonically, and I looked forward to hearing the final consumer version. Flash forward six months and a Hegel Super DAC appeared at my doorstep. I’m happy to report the production version is just as solid as the pre-production version. Initially the Super was to be priced at $399, but the current “street price” is $299.

Hegel made some very specific design decisions for the Super DAC. First, it is a USB 1.0 device that needs no drivers with any computer. This makes it truly plug-and-play, but it also limits the Super DAC to a maximum sample/bit rate of 96/24. For some audiophiles the Super’s lack of 192/24 and DSD support will make it a non-starter despite its sound quality.


Three Miniature Portable USB DACs

Hegel doesn’t supply much in the way of “under the hood” specifications, such as the DAC chip used, but according to its literature the Super does not have an asynchronous USB interface, which Hegel considers to be more marketing hype than actual technological advantage. Hegel’s published design goals for the Super were “to be extremely silent, to be able to have flat frequency response regardless of the headphone’s impedance, and to have sufficient power supply to drive even difficult headphones.” The Super does have some “trickle-down” technology derived from Hegel’s full-sized DACs including Hegel’s proprietary re-clocking techniques, and an output stage with an extremely low output impedance.

Physically the Super is simple, yet impressive. Its chassis is milled out of a single piece of aluminum that measures approximately 3 5/16″ by 1 10/16″ by 3/4″ and features an engraved Hegel logotype on the top and a satin brushed finish.

One end of the Super has a micro-USB connection while the other has a mini-stereo/optical-digital mini-jack output. The Hegel Super is capable of serving as either a DAC or a USB-to-TosLink interface. “Legacy” DACs that lack a USB connection can be used in a computer audio system via the Super. But if you do use the Super as a USB convertor, it will still only support a maximum sample bit rate of 96/24.

A Super Sound
If you favor a headphone that needs some juice to sound its best, the Super could be a perfect traveling companion. But if your go-to traveling earphone is a high-sensitivity in-ear, the Super isn’t the right DAC for you.

I tried the Super with a variety of headphones, and even with the lowest sensitivity ones in my collection, The Audeze LCD-2s, I still needed over 15dB of attenuation (using iTunes/Amarra) to bring the volume down to a comfortable listening level. With the Westone ES-5 custom in-ear I used over 40dB of attenuation. That’s a lot of excess gain in the system.

Three Miniature Portable USB DACs

The headphone that I enjoyed the most coupled to the Hegel Super was the Audeze LCD-2 (Bamboo version). The Hegel was able to propel the LCD-2s in an authoritative manner that I usually hear only from larger, AC-powered desktop headphone amplifiers. Bass was tight, controlled, but still powerful. Also the lack or electronic “grain,” due in large part to the Super’s 140dB S/N figure, contributed to the ease with which I could listen into any mix.

If your primary use for a portable DAC is with a desktop system or powered speakers, the high output of the Super will be a good thing. Hooked up to my desktop the Super sounded more like a “big boy” DAC than a portable USB device. If you listen for “pace” you’ll appreciate the Super’s ability to drive a system forward with alacrity.

 

In my desktop system the Super delivered a well-defined soundstage with precise lateral imaging. Depth was also clearly articulated, but with a hair less dimensionality than I’ve heard from my reference full-sized DACs such as the Wyred4Sound DAC-2 DSD SE. Bass extension and power through the Super, however, was equal to the best DACs I’ve heard in my desktop system including the Wyred4Sound DAC.

Although the Hegel Super does lack some features, such as DSD and 192/24 PCM capabilities, it makes up for it with its solid sound and ability to do double duty as a USB to TosLink convertor. Given the number of other portable DACs available at a similar price, the Hegel faces some tough competition. But for some prospective users, the Super’s powerful output and easy setup might be deciding factors in its favor.

Resonessence Labs Herus
The Canadian-made Resonessence Labs Herus is the most expensive portable DAC in this survey at $350 street, but it is also the most flexible in sample-and bit-rate capabilities. This lipstick-sized DAC supports PCM up to 352.8/24 as well as DSD64x, DSD 128x, and DXD files. So, regardless of how you like your high-resolution files, the Herus will play them.

Machined out of a solid block of aluminum, the Herus measures 2.5″ x 1.25″ by 0.75″ and weighs less than a pair of CD jewel cases. On one end you’ll find a full-sized USB B connection and at the other a full-sized 1/4″ stereo connection. For those audiophiles who already have a premium USB cable, Herus’ use of a regular as opposed to mini-or micro-USB could be a major advantage over some other portable DACs. Also the full-sized instead of mini-stereo plug means that you can use headphones with a standard 1/4″ plug without needing an adapter.


Three Miniature Portable USB DACs

The Herus puts out 2.4 volts from its headphone output at maximum output, giving it a slightly higher level than DACs set for the usual standard of 2 volts. Inside you’ll find an ESS 9010-2M DAC, configured using Resonessence Labs’ custom code and asynchronous algorithms that run in a generic Cypress USB interface chip. With its low 0.2 ohms output impedance the Herus should be able to handle any headphone from 32 ohms to 600 ohms with no issues.

Like the Cambridge Audio DacMagic XS, the Herus has its own volume control. But unlike the Cambridge Audio DAC, which has an analog control, the Herus adjusts its volume via the ESS 9010-2M DAC’s internal 32-bit digital attenuation control. The Herus will also work as a DAC for your iPhone or iPad with the addition of an Apple Lightning-to-USB camera adapter to connect the iPhone or iPad to the Herus. Some Android devices are also supported, such as the Samsung Tab3.

A DAC of All Trades
During my time with the Herus I’ve thrown every file format in my music library at it with 100% success and playability. The only ergonomic issue I’ve had with the Herus is that when I changed headphones the Herus reverted to full output level, which can be quite loud with high-sensitivity headphones.

Resonessence includes the following warning on their main Herus info page, “Important—Please note: some (if not all) software on the PC, MAC, and Linux will, the first time Herus is connected, set the volume to 0dB. That is, to the highest volume level. This may be very loud in the headphones. On subsequent connections the music player application will recall the last volume setting, but we have seen instances where plugging into a different USB port again sets the volume back to 0dB. Consequently, we strongly recommend that you plug the Herus into any new port on your computer with the headphones unplugged, and set the volume to a reasonable level prior to plugging the headphones into Herus.”


Three Miniature Portable USB DACs

Occasionally when I switched headphones I didn’t get music; instead all I heard was noise—loud digital-sounding noise. The solution was to close down iTunes with Amarra Symphony and then reopen them and the problem disappeared. I soon developed a standard procedure with the Herus when I switched headphones—never put on the headphones until I made sure that music, rather than noise, was coming through the drivers. [Resonessence says that this problem arises only if the user swaps headphones while music is playing. If the music is paused, this problem won’t occur.—Ed.]

I used the Herus with a wide variety of headphones. Only with the 115dB sensitive Westone ES5 custom in-ears did the Herus produce some low-level hiss and background noise. With the 112dB sensitivity Ultimate Ears In-Ear Reference Monitors hiss was reduced to the point where it was almost inaudible. Combined with any headphones of less than 95dB sensitivity the Herus amplifier section was completely silent.

 

Because the Herus does produce an output that is slightly higher than the industry standard, I was concerned whether its volume could be adjusted and attenuated so that it would work successfully with a wide variety of headphones. To get an idea of how much volume variation was needed with different earphones I made note of the comfortable volume settings for a wide variety of cans. The Westone ES5 custom in-ears required the most attenuation, -40dB. In comparison, less sensitive earphones such as the Mr. Speakers Alpha Dog headphones needed only -15dB of attenuation. The most power-hungry headphones I had on hand, a Beyer-Dynamic DT990 600-ohm resistance earphone, required only -12dB of attenuation.

The first time I heard the Herus in my hotel room at the 2013 Rocky Mountain Audio Fest, driving my Audio-Technica ATH-W3000 ANV headphones, I was transported back to the moment the recordings were made. The Herus produced a level of sound quality that rivaled any DSD DAC I’d heard, regardless of price. During the many hours I’ve used the Herus since RMAF it has continued to impress me with its transparency and ability to impose little in the way of additive colorations onto the music. I’ve been making DSD 128x recordings of live concerts since 2008, when I first started using the Korg MR-1000 DSD recorder, so I have plenty of DSD material in my music library. Whether the music is classical or acoustic folk, the Herus plays back my DSD files perfectly without a single odd noise, hesitation, or drop out.

The Herus proved to be as adept with high-resolution PCM files as it was with DSD. I usually make 192, 96, and 44.1 files from my DSD recordings using the Korg AudioGate application. Listening to the PCM files through the Herus I became aware of differences between the DSD and the PCM files. The DSD version sounded the best, followed closely by the 192/24 versions. Listening to the 96/24 versions compared to the DSD I was immediately noticed that the room sounds and trailing edges of the music were ever so slightly truncated compared to the 192/24 or DSD versions.

Switching the Herus over to desktop audio duties I was, again, impressed by its overall sound quality. Using the Herus as a source for my desktop system merely required attaching a 1/4″-stereo-to-RCA stereo pair adapter and then connecting it to a preamp via a 1-meter analog cable. Imaging was as precise as the Wyred4Sound DAC-2 DSD SE, as was depth recreation and low-level detail. When I set up a matched-level A/B with both the Wyred4Sound DAC-2 DSD and Herus connected to the Nuforce MCP-18 using my own DSD recordings I was hard-pressed to tell which DAC I was listening to; they sounded that similar to each other.

Three DACs, Three Good Choices
Of the three portable DACS I reviewed, all three offered good performance at entry-level prices. The $350 Resonessence Labs’ Herus does seem to be the most “future-proof” of the three with its support for DSD, PCM, and DXD files, so in the long run it could prove to be the best overall value. Audiophiles who prefer an analog volume control and the ability to adjust the volume from the DAC itself may gravitate toward the $199 Cambridge Audio DacMagic XS, which also supports USB 2.0 so it can play up to 192/24 files. If you have an older DAC that you still wish to enjoy with computer-audio sources, the $299 Hegel Super offers you the option of converting USB to TosLink so that you can use “legacy” DACs with your computer-audio system. And while the Super is limited by its USB 1.0 protocol allowing only a 96/24 maximum sample/bit-rate, its dual functionality is a bonus that makes it a much better value than if it were only a DAC.

Whichever of these three portable DAC options you choose, you will be rewarded by better sound and greater flexibility in headphone options due to their ability to drive headphones with more power than your computer or smartphone. Any one of them will add only a few ounces to your traveling kit, yet make the time in your hotel room or in a plane far more pleasurable.

SPECS & PRICING

Cambridge Audio DacMagic XS
Inputs: USB 1.0 and 2.0 supported
Outputs: 3.5mm stereo headphone jack
Sample/bit rates supported: USB 1.0 Mode: 16/24-bit, 44.1kHz, 48kHz, 88.2kHz, 96kHz; USB 2.0 Mode: 16/24-bit, 44.1kHz, 48kHz, 88.2kHz, 96kHz, 176.4kHz, 192kHz
Dimensions: 1.25″ x 0.4375″ x 2.125″
Weight: 3.5 oz
Price: $199

cambridgeaudio.com

Hegel Music Systems Super DAC
Inputs: Micro-USB 1.0 mode
Outputs: Mini-jack headphone and optical digital Toslink (mini-jack)
USB interface: 24-bit/96kHz, plug & play via USB 1.0 protocol
Dimensions: 1.6cm x 0.6cm x 3.2cm
Price: $299

hegel.com

Resonessence Labs Herus
Inputs: USB 2.0 supported
Outputs: 1/4″ TRS stereo headphone jack
Sample/bit rates supported: USB 2.0 Mode: 16/24-bit, 44.1kHz, 48kHz, 88.2kHz, 96kHz, 176.4kHz, 192kHz, 352.8/24, DSD 64, DSD 128
Dimensions: 63.5mm x 31.7mm x 19mm
Price: $350

resonessencelabs.com

Read Next From Review

See all

Adblocker Detected

"Neque porro quisquam est qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit..."

"There is no one who loves pain itself, who seeks after it and wants to have it, simply because it is pain..."