February
2023

Country of Origin

Netherlands

Corelli Corundum

Reviewer: Srajan Ebaen
Financial interests: click here
Main system: Sources: Retina 5K 27" iMac (4GHz quad-core with Turbo, 32GB RAM, 3TB FusionDrive, OSX Yosemite. iTunes 14.4), PureMusic 3.02, Audirvana 3, Qobuz, Tidal, Singxer SU-6 USB bridge, LHY Audio SW-8 network switch, Sonnet Pasithea DAC; Active filter: icOn Gradient Box; Power amplifiers: Kinki Studio EX-B7 monos, Enleum AMP-23R, Goldmund/Job 225; Headamp: Cen.Grand Silver Fox; Phones: HifiMan Susvara; Loudspeakers: sound|kaos Vox3awf + sound|kaos DSUB 15 on Carbide Audio footers, Audio Physic Codex, Qualio IQ; Cables: Complete loom of Allnic Audio ZL; Power delivery: Vibex Granada/Alhambra on all source components, Furutech RTP-6 on amps, Furutech DPS-4.1 between wall and conditioner; Equipment rack: Artesanía Audio Exoteryc double-wide 3-tier with optional glass shelves, Exoteryc Krion and glass amp stands; Sundry accessories: Acoustic System resonators, LessLoss Firewall for loudspeakers, Furutech NCF Signal Boosters; Room: 6 x 8m with open door behind listening seat
2nd system: Source: Soundaware D300Ref SD transport, Denafrips Terminator +; Preamp/filter: icOn 4Pro + 80Hz active filter; Amplifier: Crayon CFA-1.2; Loudspeakers: MonAcoustics SuperMon Mini, Dynaudio S18 sub; Power delivery: Furutech GTO 2D NCF; Equipment rack: Hifistay Mythology Transform X-Frame [on extended loan]; Sundry accessories: Audioquest Fog Lifters; Furutech NFC Clear Lines; Room: ~3.5 x 8m
Desktop system: Source: HP Z230 work station Win10/64; USB bridge: Singxer SU-2; Headamp/DAC: iFi iDSD Pro Signature;  Headphones: Final D-8000; Active speakers: DMAX SC5
Upstairs headfi/speaker system: Source: smsl Dp5 transport; DAC: Auralic Vega; Integrated amplifier: Schiit Jotunheim R; Phones: Raal-Requisite SR1a; Active DSP speakers: Fram Midi 120
2-channel video system: Source: Oppo BDP-105; All-in-One: Gold Note IS-1000 Deluxe; Loudspeakers: Zu Soul VI; Subwoofer: Zu Submission; Power delivery: Furutech eTP-8, Room: ~6x4m

Review component retail: €1'895

The corundum conundrum. Let's get precious. How many jewels do you wear? Ask a man whether he's got stones. Huh? Let's rewind. Corundum is another name for sapphire or ruby. It's the hardest of all gemstones after diamond. In synthetic form it's ubiquitous in automatic watch movements to protect high-friction contacts. If you still do a rotor-powered wrist watch, turn it over. Its bottom plate will be inscribed with various specs like the movement's country of origin, the case's submersion rating and lens type. Here you'll also find '23 jewels' or some such number. Those jewels are tiny artificial rubies. If the watch sports an exhibition case, you'll be able to see a few of them like below.

Artificial sapphire's ubiquity and hardness has Poland's Divine Acoustics exploit it for their Kepler footer. They also use it to decouple tweeters from enclosures. Now the thrifty Dutchmen at Akiko have embraced unspecified members of mineraldom's larger corundum group to give their 2016 Corelli passive power conditioner a shot across all three barrels. Pop its hood. You'll be greeted by hollow aluminium cylinders, one each for hot, neutral and earth. We've seen this already with DR Acoustics, Shunyata and Synergistic. Our power line's three legs split out. Each enters its own sealed chamber like a car wash before it exits on the far side to turn again into a power cord, outlet or IEC; or as in the Corelli, doesn't exit at all.

Presto, a virtual strip search during the AC's short passage through the barrels. There high-frequency pollution hitching a ride converts to heat without caps, coils or transformers. Noise replaces with silence. The secret sauce or rather powder doing the scrub is each firm's IP. We know better than expect details. Surveying this market we simply know how various other makers like Audio Magic and Verictum insist that the right mix of semi-precious stones, minerals and 'other stuff' does an ace job of attenuating UHF hash on the AC. There's also Ken Ishiguro of Acoustic Revive with his rare-earth Kiyoh mineral, an aluminum silicate; and powdered tourmaline both of which release negative ions in the high infrared range. Like others of its type, the 6.3kg Corelli is a parallel device so no gear plugs into it. It simply occupies a spare outlet in your power distributor/filter or wall, to act as a UHF trap.

Thinking readers instantly saw how convenient this makes lazy A/B. Nothing must power down or rewire. Simply un/plug Corelli and listen until you hear a difference. If you don't, save €1'895. By the way, there's no official Corelli Corundum. The Akiko chaps Sanders and Marc quietly upgraded their box without changing nomenclature or face plate. Because the press release hit January 3rd 2023, we simply know that henceforth Corelli has gotten more precious and grown truly hard stones. The gilded sticker on the back confirms it. The 'Castello connect' port is for their €1'295 Ground conditioner. And that's all corundum had by way of an intro. Ruby dearest. Conundrum solved.