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Ultrasone NAOS portable headphone DAC

Ultrasone NAOS portable headphone DAC

Clicking on the Ultrasone website is an unexpectedly pleasant experience that plunges the browser by way of video on a fly-by journey into the sunny green countryside of Bavaria. The score to The Sound of Music might as well be playing as you float above green hills, farmhouses, grazing cows, and then through a quaint boulevard in the local mountain town. Ultrasone is certainly going for an effect here to introduce themselves, but don’t get too comfortable with the expansive scenery because with its new headphone amp/DAC combo offering called the NAOS, Ultrasone is about to flip the script and go ultra-compact to the point where the NAOS makes your car’s keyless entry in your pocket look big. By way of the minute NAOS headphone amp/DAC combo Ultrasone is looking to do nothing more than solve an unavoidable existential quandary of our modern audiophile existence. The quandary goes something like this: “Sure, I have my prized hi-fi set up waiting for me when I get home from the office, but I am stuck at the [pick one: bus-stop, post office, airport, etc.]. What am I going to do until I get back home?”

, Ultrasone NAOS portable headphone DAC

One answer the NAOS provides to this frustratingly familiar audiophile lament is to attempt to revive that smart phone in your pocket that you left for dead in regards to quality music playback. The versatile NAOS is not just pigeon-holed to mobile phones mind you, the NAOS’ larger mission is to bring all your downloaded and streaming music files up to par in a one-size-fits-all powerhouse small enough to get lost in your jeans pocket. The NAOS steps out boldly front and centre to meet its competitors priced at an affordable £199, which means if inclined most of us have no further excuse for leaving it up to Samsung or Apple to convert and amplify our source files behind a black curtain of secrecy and profit enhancing built-in cheap components.

The NAOS is covered in an inconspicuous brushed aluminium housing and measures 46mm long × 18mm wide x 6mm thick. At this small size, and weighing in a negligible 6 grams you can be sure that if you are hooked up to your mobile device the size of the NAOS will not affect any of the lifestyle activities you were planning like going for a walk, a jog, or a bike ride. Not only is the NAOS tailor made for portability, Ultrasone has gone the extra mile to make the device friendly to any platform be it Apple, Android, PC, high quality source, or low quality source. This catch-all use it anywhere, anyhow mentality is further bolstered by the number of attachment components that comes with the product in its simple black carrying case. From the Ultrasone website, “NAOS works with smartphones, tablets, notebooks and desktop computers. To this end, it comes with cables for micro USB, USB C, Light­ning, and USB A. NAOS uses the connection not only to transfer data, but the compact DAC also draws its power using the same cable, so no additional power supply is necessary. NAOS works with iOS, Mac OS, Android (USB OTG function) and Windows (driver in­stall­ation). Laptop, smart­phone, desktop PC or tablet. Included with the NAOS are corresponding cables for micro-USB, USB-A, USB-C, and Lightning connections. “

The digital to analogue converter residing in the NAOS allows a listener’s digital files or streaming source to be converted up to a resolution of 192 kHz and a word depth of 24 bits. After NAOS’ runs its conversion process, the new analogue signal is run through the NAOS’ high-performance amplifier where it is said to be ‘optimised’ for use among a wide range of headphones. I was able to put some specifics to Ultrasone’s claim by auditioning many sets of in-ear and over-ear headphones, but more on this later. It is a good bet that the majority of potential NAOS users will find the smart phone the most appealing device to use with the NAOS, but please note that it can also be easily plugged into your home base computer or with your loudspeakers system up the signal chain from even a robust power amplifier. Ultrasone is certainly not worried about the NAOS swimming in the deep end of the pool.


With the deserved focus on the NAOS’ versatility and functionality, let us not lose the focus that the NAOS is, above all, an audio pleasure-enhancing device. To gauge this aspect of the NAOS’ performance I concentrated on auditioning Bill Wilson’s nearly forgotten and underappreciated classic Ever Changing Minstrel [Columbia]. The track ‘Long Gone Lady’ is an excellent piece of music to gauge the nuances of audio equipment’s presentation as there is little production razzle-dazzle to distract the listener. With the formidable and straight shooting 1973 Nashville studio musician powerhouse in high gear backing Mr. Wilson, the ‘Long Gone Lady’ track stands out on the album with an equal mix of soulful acoustic guitar, strong male vocals, nearly naked bass, and backing female vocals that are all expected to stand out in the mix, share the space, and play nice in the sandbox together. My audition of this track and the album as a whole through the NAOS included a wide variety of reputable in-ear headphones: RHA MA750s, Westone W10s, 1MORE Triple Drivers, and NuForce Primo 8s to throw a few names out. Across the board with this slate of $100-$200 in-ear headphones the positive impact of adding the NAOS to the listening experience with high quality FLAC files from TIDAL’s iPhone app was undeniable. The NAOS added immediacy to the pulse of Bill Wilson’s music as if suddenly your seats at his concert were upgraded from 150’ away in the balcony and you were zoomed right into the orchestra pit. The treble, midrange, and bass were all enhanced and immediately woven into a remarkably defined and well managed soundstage. The presentation upgrade from the NAOS was so obviously engaging that It was quickly unthinkable to simply plug headphones into my iPhone 6S or desktop computer as I moved on in the audition from high quality FLAC steaming to a few lower fidelity sources like a simple Spotify steam, listening to music based podcasts straight off of iTunes, or my collection of first generation MP3s. As advertised by Ultrasone, the NAOS’ top to bottom enhancement factor was apparent across the board on all of these sources when using any of my headphones in the sub £200 category.

, Ultrasone NAOS portable headphone DAC

It should be noted that when the NAOS was paired with headphones approaching the £250 price barrier like the Audio Technics ATH-MSR7 (£200) and Final in-ear F7200’s (£400) that the NAOS was much less effective. This loss of utility with the more expensive (and presumably higher performing) cans seemed to be consistent and ultimately I considered it inconclusive if the NOAS substantially enhanced the music after breaking the $250 mark with the selected headphones listed above. Fortunately for Ultrasone most of us live in the world (especially on the go) where the virtually limitless variety of superior quality headphones under £250 will do just fine. In this vast price plateau the NAOS was able to augment virtually all facets of the musical presentation (treble, bass, mid-range) regardless of the quality of source. Sure, FLAC files sounded better through the NAOS than my basic MP3s downloaded originally in 2005, but the NAOS enhanced both sources proportionally to their base quality. It did not seem that the NAOS’ benefits were relegated to any particular side of the sound experience exclusively like treble or bass for example, so be cautioned against embarking on a quixotic adventure with the NAOS looking for your pet sonic upgrade. The NAOS seems well applied to those looking for an all-around audio improvement from their device or computer of choice. If your selected playback device happens to be operating on its own battery please be aware that using the NAOS will put a sizeable dent in battery life and any volume controls that are part of your headphone assembly will not work. However, these particularly inconveniences seem like a small price to pay when you are stuck on the jet-way in an economy seat and the NAOS can help turn your cramped middle seat and modest travel headphones into the next best thing outside your home listening room. Most of us are going to have to work very hard to find a set of affordable headphones that are not enhanced in a substantially positive way by the addition of this nearly invisible and weightless pocket sized dynamo.


  • Type: Solid-state high-resolution digital-to-analogue converter/headphone amplifier.
  • Digital Inputs: Micro-USB, Lightning, USB (T yp A), USB-C
  • Analogue Outputs: 3.5mm mini-jack
  • Frequency Response: 10 Hz–30 kHz
  • Dimensions (H×W×D): 6 × 18 × 46mm
  • Weight: 6g
  • Price: £199

Manufacturer: ULTRASONE AG

Tel: +49 (0) 881 901150 0

URL: ultrasone.audio

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