Country of Origin


D/D converters

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: TBA

Terminator DSP board from my review of the upgraded module

Roundabout. "Hope you're well. Have been using a Denafrips Terminator for about two years. Am very pleased on price/performance. Listen mostly to 44.1kHz 16 bits. Have a chance to grab an Aqua LaScala2 Optologic and wanted your thoughts on gains. Like you I value tone density but not at the sacrifice of inner detail. My preamp is a modded W4S STP and my amp a modded Rogue Medusa that runs two 12AU7 which I regularly roll. Speakers are Alta FMR2." That was reader Paul.

"Have you done the Terminator DSP board upgrade? It's about €200 and a major resolution update. It's plug'n'play. I've got the review on it. That's what I'd go with if I were you."

"Thanks for reply. Have not and will take your advice. I presumed incorrectly that the new board only impacted DSD playback. I'll reach out to Alvin."

Paul's next email was on having "found the Kitsune modified Singxer Su-1 with Intona USB isolator and super-short Intona premium HDMI cable to be the best way to get I²S into the Terminator. I tried many combos/products, several a lot more expensive."

"I²S is definitely the preferred entry," I confirmed.

"Looks like your review tapped out Alvin, 6-8 week lead time on the new DSP board."

Some time passed. Suddenly Paul was back. "I imagine you get hit up constantly with suggestions but you owe it to yourself to see if Kingwa from Audiogd will loan you for review his new USB DDC with regenerative power supplies, FPGA and I²S out (among others) into the Terminator. Eclipsed the improvement the new board made with the Terminator which I would agree was significant. Kingwa has been doing digital and power supplies right for a long time without much accolade but this is easily his best effort and absolutely sublime with the Terminator via I²S."

I told Paul that I was perfectly happy with our Soundaware D300Pro which reclocks incoming USB and outputs it I²S over HDMI to our Terminator whilst doubling as SD card transport.

"Oh good, somehow I missed that you had settled on a solution for I²S. Something special about this DI-20 however. I understand that Denafrips have a DDC of their own in the works. Would be nice if it could double as a Roon endpoint à la the Metrum Ambre. Thanks again for all of your great advice, makes my life easier. I grabbed a Pass XA25, what a wonderful little amp. Am in conversation with Veronica in Cambridge about a pair of Kroma Mimí when they arrive."

Exit. Paul's last email had pricked up my ears. I contacted Alvin Chee of Vinshine Audio in Singapore. What did their global marketing manager know about these Denafrips plans? "News spreads fast. Yes, it's coming. No, they are coming. Three models, entry, premium and flagship. They are all pure digital-to-digital converters. The entry-level model converts USB to AES/EBU, coax, Toslink and I²S. The premium model adds a fifo buffer and femto clock. The flagship model adds mil-spec temperature-stabilized crystal oscillators for the very best in reclocking. It will be an exciting year for Denafrips."

Unlike S/PDIF, USB embeds no clock signal. The clock is either on the send end (synchronous) or receive end (asynchronous). In high-end audio, the latter is preferred. It puts the clock far closer to the D/A converter, thus past the digital cable and its connectors. Hifi designers can upgrade their clock over whatever a generic computer might use. Yet replace an upscale DAC's own USB input—it's likely galvanically or optically already isolated—with a dedicated USB bridge. That connects its reclocked signal to one of your DAC's S/PDIF inputs. Why should that improve the sound? How many digital clocks in series do we really need?

Our music iMac connects directly to the  Internet router by 30m CAT5  unless a streamer/server review requires wired access for a tablet remote. Then the Tp-Link switch adds Ethernet sockets.

As my drawing shows, a super-capacitor powered Soundaware D300Ref acts as USB bridge in our main system. It generates a signal with dedicated clock line as I²S over HDMI. My work desk uses the battery-powered Audiobyte Hydra X+ to generate two S/PDIF outputs, one into a COS Engineering H1 headphone amp, one into a pair of active Fram Midi 120 speakers. Experiments with Mutec's MC-3+USB reclocker in both systems were just as audible. So like reader Paul with his DI-20HE Audiogd bridge, I'm convinced. Such devices can make appreciable improvements even to ambitious digital front ends like our Terminators. In fact, they can even make 'audiophile' network switches redundant. That I recently encountered with Fidelizer's Etherstream. For streaming Qobuz/Tidal, it only made a difference when I bypassed the D300Ref. I'm simply hazy on the exact mechanism whereby/why double clocking nets its improvements. Actually, I'd prefer it if external black boxes couldn't better already costly digital converters. But, my ears can and do accept and enjoy audible benefits even without explanations.

Once Denafrips review samples drop, this story will continue. For now, think of USB reclockers a bit like yesteryear's disc transports. Back when, listeners were surprised that different disc transports sounded different. It's why Esoteric's massive VRDS sleds shown at right became popular. It's why, when Philips discontinued the CD-PRO 2 transport, Vienna's StreamUnlimited launched the PRO 8. It shows up already in a dedicated top-loading Pro-Ject transport and in Gryphon and Accustic Arts players and transports. A forthcoming Gold Note machine will use it as well.

It all revisits that earlier breach of the bits-are-bits argument. Transport differences refuted that only the 'A' side of D/A conversion mattered; that any wobbly old plastic sled could do the same job. The 'D' side—when signal is still in the digital domain—matters as well. It includes digital wires. It's why today, better routers, network switches, Ethernet isolators and USB bridges all have their rightful place in a no-compromise hifi system. Sometimes in fact, there won't be sound without one. My Polish computer speakers for example lack a USB input. To enter them digitally, I need S/PDIF. From my stock HP work station? Audiobyte Hydra X+ to the rescue. Since that already supplied the speakers, I checked whether the headphone amp with USB DAC would sound better USB direct. Not. Now it gets its own S/PDIF signal from the Audiobyte's BNC port. A nice side benefit is that I needn't change USB devices in Windows whenever I switch from desktop speakers to headphones and back.

… to be continued…