Reviewer: Srajan Ebaen
Financial interests: click here
Sources: 27" iMac with 5K Retina display, 4GHz quad-core engine with 4.4GHz turbo boost, 3TB Fusion Drive, 16GB SDRAM, OSX Yosemite, PureMusic 3.01, Tidal & Qobuz lossless streaming, COS Engineering D1 & H1, AURALiC Vega, Aqua Hifi Formula, Fore Audio DAISy 1
Preamplifier: Nagra Jazz, Wyred4Sound STP-SE MkII, Vinnie Rossi LIO (AVC module), COS Engineering D1
Power & integrated amplifiers: Pass Labs XA30.8; FirstWatt SIT1, F5, F6, F7; Bakoon AMP-12R; Crayon Audio CFA-1.2; Goldmund Job 225; Aura Note Premier; Wyred4Sound mINT; Nord Acoustics One SE Up NC500MB monos; LinnenberG Audio Allegro monos
Loudspeakers: Audio Physic Codex; EnigmAcoustics Mythology 1; Boenicke Audio W5se; Zu Audio Druid V & Submission; German Physiks HRS-120; Eversound Essence
Cables: Complete loom of 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 components, Titan Audio Eros cords between wall and conditioners and on the amps
Equipment rack: Artesania Audio Exoteryc double-wide 3-tier with optional glass shelves, Exoteryc Krion and glass amp stands [on loan]
Sundry accessories: Acoustic System resonators
Room: Rectangular 5.5 x 15m open floor plan with two-storey gabled ceiling, wood-sleeved steel trusses and stone-over-concrete flooring
Review component retail: €2'475 [excl. VAT]

Below at the Dutch XFi show 2017, with Metrum's own dipole speakers which won't go into formal production but remain their in-house design reference.
Jade, Amethyst and Onyx on top shelf, Adagio and Forte on bottom shelf for size reference.

Have stones. Will play. Kahunas or cojones? Not this time. Today we get properly jaded. It's about the new top model within the 3-deep semi-precious group of Cees Ruijtenberg's Metrum Acoustics D/A converters. It starts with Amethyst, then middles with Onyx. In fact, Onyx and Jade are very similar. Jade simply adds remote volume by way of variable reference voltage for its R2R ladders. "Setting volume to 12:15 gives you the RedBook standard 2V out. Jade and Onyx share the same mother board. A jumper setting on it sets it to fixed or variable. Onyx gets a one-button remote, Jade a 4-button remote. Our flagship Pavane and Adagio use four not two of our DAC TWO modules per channel. Both are dual mono and even the digital input board has its own power supply. In these big fellas, the boards connect to each other via fast optical logic for true galvanic separation. To author two more affordable versions and get almost the same properties was quite the challenge!" Indeed.

"To reduce cost but maintain quality we did everything possible to optimize our signal routing. Proper grounding was probably the biggest challenge. Mixed disciplines each want their own approach. Digital asks for massive ground planes. Analog works best with a star ground. This means that ground planes can be used but should connect to just star ground and work as only static shields. Further we did everything to reduce power consumption. That's now down to 8 watts max and mostly dominated by the four converter modules. I've attached a screen capture which shows the result of this approach. Here 0dBFS equals the max Redbook signal of 2V/RCA and 4V/XLR. Input signal was a 1kHz sine wave at -120dBFS. The white cross on the 50Hz line is where we measured hum. As you see, this is extremely low and not visible above the noise floor. Furthermore, the noise floor is a lovely -150dBFS in the most sensitive area of our ears. What's left is the performance of using two DAC TWO modules in balanced mode. That will be for you to judge." No pressure.

Jade versus...

...Onyx, showing the addition of the motorized pot as the distinguishing feature. With Jade positioned at €2'450, it stares down Schiit's $2'299 Yggdrasil but adds remote volume. This involves no bit stripping because it's not on-chip digital attenuation. It's not a basic pot on the analog outputs either. It addresses circuit gain directly. That's vaguely related to how Bakoon do it for their Satri circuit and exactly how Etalon Sound vary their R2R DreamDac's output; or Cees that of his €6'950 Adagio flagship. Usually manufacturers complain when a reviewer references their product to a competitor's which costs 60% less but performs on par. "You just killed my sales" was one such recent email. Today, Cees would have competed squarely against himself to only blame himself. If I'd had an Adagio. I didn't. To learn how big or small the sonic gap separating them might be remains for another reviewer to say. I can merely express honest admiration that such advanced tech just jumped down in price by such a significant margin. It seems nearly saintly. We'll get back to that.