November
2018

Country of Origin

Italy

CD-1000Mk11 four ways

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, Fore Audio DAISy1, COS Engineering D1, Denafrips Terminator, Soundaware D300Ref,  AURALiC Vega 
Preamplifier: Nagra Classic, Wyred4Sound STP-SE Stage II, Vinnie Rossi LIO (AVT module)
Power & integrated amplifiers: Pass Labs XA30.8; FirstWatt SIT1 monos, 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; Albedo Audio Aptica; EnigmAcoustics Mythology 1; Boenicke Audio W5se; Zu Audio Druid V & VI & Submission; German Physiks HRS-120; Eversound Essence
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: €3'800 in base version, €4'800 in deluxe version with USB and PCM1792A; $2'950/ea. for PSU-1000 and Tube-1006

Against itself. As Gold Note's German-born new marketing director Marie Greggers promised, it'd be a fun and unusual ride. "Something a bit different" as she put it. Because the Italian team around Maurizio Aterini devised an add-on inductive power supply upgrade for all their 1000 range models except power amps; and because they also finalized 6- and 12-tube external output stages which can enhance the transistor outputs of their DAC/streamer, phono stage, CD player and preamp… I could pick one of those plus one of the tubers, then compare the standalone machine against itself with two duet combos and one trio. I selected their new MkII CD-1000 as the only one we hadn't reviewed already. And because with tubes I don't subscribe to the more-is-merrier routine, I asked for the Tube-1006. Forget the French ménage à trois. This would be an Italian quattro: CDP solo (€4'800); duet with tubes (€7'750); duet with bigger power reservoir (€7'750); trio with tubes and bigger power reservoir (€10'700). While listing euros, just the player without USB but with a lower-spec BurrBrown converter is €3'800.

The Golden Squad of Florence

Rewind. All hifi electronics are just modulated power supplies. Words to that effect remind us. Just as a harpist fingers her strings, an audio signal simply plays on our gear's power supplies. It's not separate from AC power like pure snow which never comes down the mountain. As a result, better/costlier components distinguish themselves primarily on the quality of their power supplies; and how well their magnetics and AC connection are isolated for optimal noise attenuation. A logical upgrade path would now want to replace a lesser with a morer supply and call it a day. And in the realm of small wall-wart components, replacing cheap switch-mode bricks with better linear supplies is common and easy. The original power supply was separate to begin with. But because standard components include theirs in the main chassis, it's no dice. They are stuck in first or second gear. They can't shift up and go faster because built-in supplies are inextricably tied to gain, logic and digital circuitry. Here Maurizio strategized differently for his 1000 Series kit. Part of its design brief was this built-in upgrade path from the very beginning. As the next photos show, the external power supply and tube output stage circuitry occupy as much real estate as the entire component to which they dock. You'd not fit everything into one chassis. Now thinkers wonder. What happens to the power supply inside our CD player? Does it get bypassed/chucked altogether; or assigned to a secondary task whilst the outboarder takes over primary duties? The answer: the external supply completely bypasses the internal one, hence the power cord on the main unit can be removed.

Unlike conventional tube buffers with zero voltage gain, Gold Note's Tube-1006 tacks onto the transistor outputs with 3.5dB of active voltage gain, swings a max 15Vrms on XLR and half that on RCA with six 6n1p triodes and no coupling transformers on the i/o. Technically, this works out to a hybrid solid/hollow-state output. Its S/N ratio is >98dB across the audible bandwidth. The output impedance of this dual-mono class A circuit is below 600Ω and its power consumption is 40 watts. Gold Note describe it as a "proprietary totem-pole design with six independent stages per tube and ultra-wide bandwidth with the lowest distortion. Four of the triodes are dedicated to gain, two are drivers."

Available chassis colours are black, silver and champagne; and vertical trim options are black, silver or Walnut.

The 20kg PSU-1000 "super inductive dual choke hybrid design features an inductive filter on the analogue stage and a dual choke design controlled by a double inductor driving both negative and positive high-current stages. It perfectly filters the signal voltages to eliminate interference and electrical noise from the AC power. With its massive 1Kw rating, it provides a shield from the power grid to achieve complete insulation. That creates an ideal working environment in which the electronics perform their best." The PSU-1000 with auto line switching is powered by five transformers. Three are dedicated to the power supply, one to the inductive choke filter and one to galvanic insulation of the audio stage. There are seven rails total: +12V, 18V and +5V for the logic circuits; ±12V for the inductive noise filter; and (only for the P-1000) ±28V for the inductive noise filter. Performance specs are line and load regulation tolerances of 0.05% for all outputs and AC line noise rejection of >80dB. Where the Tube-1006 sports a frontal mute switch next to its power button, the PSU-1000 makes it power polarity instead.

As Marie suggested, this would be an unusual ride. How much relative sonic gains would each of these outboard boxes contribute on their own? Would the power supply trump the tube output stage or vice versa? Doubled up, would gains double up too or pull one of those 'greater than the sum of the parts' stunts? Where so much digital discourse revolves around conversion silicon, sample rates, formats, MQA and FPGA trickery, this assignment would focus down on a beefier power supply and scaled-up output stage. We'd bypass fascination with the digital side altogether. We'd give precedence to purely analog design chops.

Before we listen in, prospective buyers will want to know how the CD-1000 MkII differs from the original I reviewed here. Maurizio explains: "CD tray and servo were updated to higher customised quality standards with the Austrian Stream Unlimited aluminium JPL2800 SilverStrike mechanism [also used in the €20K+ dCS Rossini – Ed] instead of original JPL2580. For it we also built a new solid aluminium plinth behind the 15mm front panel to insure best stability and mechanical isolation. The layout of the digital and analog boards powered by a linear supply has been changed and the various power supply transformers were upgraded from the earlier blue Talema range to now Italian custom magnetics."

To those wondering why this transport's inherent DVD/SACD fitness doesn't translate, "we decided to not support SACD because it would have meant a discontinued Sony/Philips or standard Blue-ray servo. Instead we are evaluating a limited SACD edition of 100 for our upcoming top-loading CD player developed with Michael Jirousek, chief engineer of Stream Unlimited who visited us last September to discuss such a project. The 100-piece limit will be due to them having reserved the last 100 Sony/Philips servo boards necessary for SACD."  … to be continued…