March
2020

Country of Origin

Korea

X7-DAC Femto & Clean Power

Reviewer: Srajan Ebaen
Financial interests: click here
Sources: Retina 5K 27" iMac (4GHz quad-core with Turbo boost, 32GB RAM, 3TB FusionDrive, OSX Yosemite. iTunes 14.4), PureMusic 3.02, Audirvana 3, Qobuz Hifi, Tidal Hifi, COS Engineering D1, Denafrips Terminator, Soundaware D300Ref,  AURALiC Vega 
Preamplifier: Vinnie Rossi L2 Signature with WE VT52/300B or Elrog 50/300B, Nagra Classic, Wyred4Sound STP-SE Stage II, Vinnie Rossi LIO (AVT module)
Power & integrated amplifiers: Pass Labs XA30.8; FirstWatt SIT1 monos, SIT3, F5, F6, F7; Goldmund/Job 225; Aura Note Premier; Wyred4Sound mINT; Nord Acoustics NC500 monos; LinnenberG Audio Liszt monos
Loudspeakers: Audio Physic Codex; Cube Audio Nenuphar; Kroma Audio Mimí; Albedo Audio Aptica; EnigmAcoustics Mythology 1; Boenicke Audio W5se; Zu Audio Druid V & VI & Submission; German Physiks HRS-120; Eversound Essence; Fram Midi 150 & 120; Acelec Model One
Cables: Complete loom of Allnic Audio ZL3000 and Zu Event; KingRex uArt, Zu and LightHarmonic LightSpeed double-header USB cables; Tombo Trøn S/PDIF; van den Hul AES/EBU; AudioQuest Diamond glass-fibre Toslink; Black Cat Cable redlevel Lupo; Ocellia OCC Silver
Power delivery: Vibex Granada/Alhambra on all source components, Vibex One 11R on amps/sub
Equipment rack: Artesania Audio Exoteryc double-wide 3-tier with optional glass shelves, Exoteryc Krion and glass amp stands 
Sundry accessories: Acoustic System resonators
Room: 4 x 6m with high gabled beam ceiling opening into 4 x 8m kitchen and 5 x 8m living room, hence no wall behind the listening chairs
Review component retail: $1'200 for DAC, $1'100 for upgraded power supply

"Hello. My name is Gunhee Lee. I'm working for South Korean company Soundcat. We wish to introduce you to two excellent products whose planning, development and production we participated in. These are the JAVS X7-DAC Femto priced at ~$1'200 and the matching Clean Power supply priced at ~$1'100. We would be grateful if you could review these. The website for the products is here but only the models we want reviewed have been translated into English. Soon we will begin to sell our products through eBay."

Surfing to Gunhee's product pages, the power supply turned out to be a 12V/10A ferric phosphate battery which is claimed to be safer than Lithium Ion equivalents whilst lasting 5-6 times longer. This battery is augmented by 6 x 10-farad Panasonic ultra capacitors. The unit can supply three devices with up to 125 watts total whilst delivering a claimed 8A of instantaneous current (i.e. in just 0.012 seconds). An external 24V/7A DC power brick charges the Clean Power unit which, aside from two parallel 12V/4A power outlets, also has a USB loop. A USB 3.0 B input receives your computer's USB signal, replaces its 5V dirty power with virgin battery power, then spits out fully isolated USB via its USB A port. Charging from empty to full is said to take 3.5 – 4 hours. The real estate you give up for it is just 21.5 x 27 x 6.5cm DxWxH. Weight is 3.5kg and finish options are black or silver. The JAVS aka Jineung Audio & Video Systems logo shows green for charged, red for currently charging, orange for less than 15% remaining charge. The mode switch can prompt recharging which otherwise kicks in automatically when a minimum charge threshold is breached.

The DAC with its 12V/DC input has the usual inputs of coax, Toslink and USB B as 3.0 and mini (a TDS54528 isolates a PC's 5V USB power and the USB transceiver is an XMOS xCore-200 chip). There's also AES/EBU and what in this price class is very rare I²S over HDMI. The two S/PDIF ports transformer couple for galvanic isolation. The femto clocks of the model name are WX-K013 units for the two A/V sample-rate families. XLR and RCA outputs can be variable or fixed via rear toggle. Volume control is Asahi Kasei's 32-bit code on their AKM 4497EQ Velvet Sound Verita chip which supports 384kHz PCM, DSD256 and full MQA.

Four LME49710MA opamps handle I/V conversion, another two the differential gain block. The balanced and unbalanced outputs see OPA 2134 opamps. 6.3mm and 3.5mm headfi ports are fronted by an AD8397 opamp plus miniature discrete class A modules. On the low-impedance mini jack, headphones see up to ±5Vpp/160Ω. The higher-impedance big jack does double that into 600Ω. If you've kept a careful parts count, you saw that rather than discrete, the X7 exploits a plethora of modern integrated circuits. Its dimensions naturally mirror those of the Clean Power to stack neatly. Weight is 2.6kg.

Meanwhile Soundcat are an Asian marketing/distribution firm who import IEM brands like 64audio, Etymotic, Ultimate Ears, Westone and more; personal audio from audioengine, Fender, iFi and others; cable brands like Cardas and mogami; and sundry pro-audio and microphone products. Today's JAVS seems to be their house brand. That implies global exports. As we've read, said clearing house will be mail-order giant eBay. It explains Gunhee's interest in an English online review. But why ever did I open today's product intro with the power supply?

D/A converters are multitudinous. Battery-powered ultra-cap enhanced PSU with support for three smaller components are not. If the X7 doesn't have your interest because you're already set on converting digital to analog, the Clean Power still might deserve your attention. For many readers, it could be the cherry of this report. That's why it came first. As to the country of origin, South Korea is quite the hotbed for specialty hifi brands. Think of Allnic, April Music, Astell & Kern, Aurender, Emillé, Metal Sound Design, Simon Audio, SOtM, VRF/Rendezvous and Waversa for just a few. Hyundai, Kia and Samsung for automotive and IT needn't even be mentioned. As Poland has arguably become Germany's most resourceful European competitor so South Korea have nipped at Japan's heels for years whilst in general, Chinese exports still focus more on the mass market. Did you know that Goldmund's biggest export market is South Korea? Now the scene is set for new brand JVAS to make its debut in our pages. If you still wonder how the Soundcat name came about, their parent company Catsco's HQ in Seoul are in the Cat's Tower. Meow. Tracking my sample package to learn its route, I saw Goyang-Si to Incheon-Si Korea ⇒ Guangzhou China ⇒ Köln Germany ⇒ Stansted UK ⇒ Dublin Ireland. Quite the globetrotter. How EU customers will see VAT—prepaid or collected COD—remains to be seen.

… more to come…