Celsus Sound Companion One DAC/headphone amp

While home audio systems have been steadily improving in performance for many decades, you only have to go back a few years to find a time when portable audio was a cruel joke that no audiophile would take seriously. This all changed with the introduction of personal music players like the Apple iPod, and has been progressing at a rapid pace with many new portable DACs, headphone amplifiers, and high resolution music players. Now the Celsus Sound Companion One looks to take that progression a few steps further.

Celsus Sound may be a new name, but the company was founded by a certain Jason Wei-Min Lim, the former CEO of NuForce, so there is a track record to back it up. What Lim has created for his new venture is a true Swiss Army knife of portable DAC amps, ticking off just about every box on the wish lists of on the go audiophiles.

For starters, the Companion One can connect to just about any type of device you might want to use for portable music listening, including Android, iOS, Mac, and Windows devices. It can also do this using either a wired, or a wireless connection. It can decode just about any type of file you want to throw at it including DSD64, DSD128, and PCM up to 384/32 using a wired connection, plus high res PCM up to 192/24-bit over a wireless connection.

Looking kind of like an Apple iPhone that went out on a fast food binge, the Companion One’s height and width fall right between the iPhone 6 and 6 Plus, although it’s a bit more than twice the thickness of either one. A quick check on my postal scale revealed that it actually weighs in at a little over 255g… about twice that of a standard iPhone 6.

Why all of these comparisons with the Apple iPhone? Basically, it’s because the Companion One appears to borrow heavily from the iPhone 6’s styling, and the two look like they were meant to go together. The front and rear surfaces are Gorilla Glass, wrapped with a slightly curved satin metal frame. Even the buttons and ports look familiar. In any, er, case, the fit and finish of the Companion One is exceptional, and the whole unit positively oozes quality and luxury. In addition to the Companion One itself, you get an extra luxurious leather carrying case that even smells nice, a screen protector, and a set of cables to handle connections to an Android with OTG, iOS Lightning device, PC, or Mac computer, and even a 30‑pin Apple cable for your older iDevice.

On the hardware side of things, the Companion One uses the ESS ES9018K2M DAC to convert all of those files, then delivers its output to your headphones via OPA1612 and AD8397 opamps. Celsus specifies the output voltage at 3Vrms in high gain setting and half that in the low gain setting, delivering 160mW into a 32 Ohm load and 28mW into a 300 Ohm load. While that doesn’t exactly make it a powerhouse, it should drive most headphones without problems.

The controls and ports on the Companion One are deceptively simple, starting with the two mini USB ports on the bottom, one for data and one for charging. Moving to the top you’ll find a pair of 3.5mm sockets covering line and headphone outputs, along with a 3.5mm S/PDIF digital output. Finally, along the sides there are a total of six buttons, three on each side. Those on the right side control volume up and down plus power, while the three on the left side are a bit more tricky. The lower button switches between the two gain settings, so you can match the volume range to the sensitivity of your headphones. A tiny red LED between the volume buttons lets you know when you’re in the high gain setting. The upper button toggles between the USB and Wi-Fi inputs, while the button in the middle has two functions. When the Companion One is in Wi-Fi mode it selects between the AP connect mode for a one to one connection with your source, and client mode where the Companion becomes a device on your home Wi-Fi network. Change to a wired connection and the middle button then allows you to toggle between full speed (12 Mbps) and high speed (480 Mpbs) connections. All of this presents a bit of a learning curve, not helped by the almost total lack of indicators to tell you what settings are selected. There’s no fancy display or touch screen, just a row of four blue LEDs to indicate the battery level, and a single multi-coloured function LED that blinks and flashes between four different colours in a cryptic set of coded messages to tell you what’s happening. There’s even an occasional voice prompt over the headphone output, but wouldn’t it be easier to add a few additional indicators next to each switch to spell things out a little more clearly?

Making a wired connection between the Companion One and my iPhone 5 proved to be a snap, with the supplied five inch Lightning cable allowing for an easy plug and play hook up. Best of all, you don’t need to use Apple’s camera adapter cable to make it all work. The wireless connection was also relatively straightforward after I switched my phone over to the Companion One’s Wi-Fi signal. I also wanted to play high res files, so I needed to make a wired connection to my Windows laptop. This proved to be trickier than expected, with a few hurdles to overcome. First, you need to install a set of drivers downloaded from the Celsus One website, and even this process proved to be kind of buggy. Once that was sorted, I found that because The Companion One uses ASIO rather than WASAPI drivers, it didn’t want to play nice with my Foobar 2K audio player. Apparently there are some plug ins you can add to make it all work, but I chose to take the easy way out and simply used the JRiver player instead.

I auditioned the Companion One with a pretty wide range of headphones, including the Sennheiser HD-650 (later version), Ultimate Ears UE-10 IEMs, HiFiMAN RE-600S, and the fairly tough load of the HiFiMAN HE-5s. Even with the HE-5s, I never felt that the Companion One was about to run out of steam, and the sound remained clear and dynamic.

All of this sleek loveliness and technical versatility would be for naught if the Companion One couldn’t deliver the goods sonically, but what immediately struck me was how the basically neutral tonality of the Companion One allowed the true character of the recording and connected headphones to shine through. The lower octaves from 300Hz down were particularly impressive, and on the Keith Richards track ‘Words Of Wonder’ the Companion One could take a headphone that tends toward a fat bass sound such as the Audio Technica ATH-M50X, and whip it into line so the bass remained tuneful and clear. When I played the same track over the UE-10s, the dynamic snap of drummer Steve Jordan’s snare drum came across with startling realism, along with the harmonic richness of Keith’s guitar.

For the high res experience, I listened to David Chesky’s ‘Jazz In The New Harmonic’ playing 192/24 files downloaded from HDTracks. This is an exceptionally natural sounding acoustic jazz recording, and via the Companion One it drew out all of the tonal colours from drummer Billy Drummond’s various cymbals, along with the power and detail in Peter Washington’s acoustic bass playing. I didn’t name a track here, because once I started listening, I just played the entire album, front to back.

With record after record, and through all kinds of headphones, I soon came to the conclusion that the Companion One was really more like a tool that allowed me to audition recordings and headphones, than a device with a sound of its own. It always remained neutral and simply let me hear the best of whatever it was connected to.

While $595 (US) might seem like a lot of money for a portable DAC amp, I know of many audiophiles who would happily spend more than that amount on tweaks where the sonic benefits are subtle at best. The Companion One is an auspicious achievement for a new company, and I’ll be eagerly waiting to hear what else they might have tucked up their sleeves.

Technical Specifications

• Type: Portable digital-to-analogue converter and headphone amplifier
• Digital Inputs: One Micro-USB B 2.0 input (asynchronous, OTG, supports ASIO); Wi-Fi (Supports uPNP, Airplay, DNLA, Qplay)
• Digital Outputs: One Mini-TOSLINK optical S/PDIF
• Analogue Outputs: Two; One line level, one headphone level, single-ended (via 3.5mm jacks)
• DAC Resolution/Supported Digital Formats: USB; PCM files from 16-bit, 44.1kHz to 32-bit, 384kHz. DSD files from DSD64 to DSD128, DXD; Wi-Fi; PCM files from 16-bit 44.1kHz to 24-bit 192kHz .
• Frequency Response: 20Hz – 22kHz, +0dB, -0.5dB
• Distortion (THD + Noise): 0.001% (0dB, 10k Ohm load)
• S/N ratio: > 115dB (at 2Vrms)
• Crosstalk: < –110dB
• Dynamic range: > 115dB
• Output power: 160mW @ 32 Ohm, 28mW @ 300 Ohm
• Dimensions (H×W×D): 145 × 76 × 17mm
• Weight: 260g
• Price: $595 (USA), €595 (EU, currently no UK distributor)

Manufacturer: Celsus Sound

URL: www.celsus-sound.com