To make sure I wasn’t losing fidelity with the iUSBPower on account of cheap $5 USB cables that fail to meet USB test specifications, I recruited the assistance of nearby KINGREX. With headquarters in New Taipei City, they were only a 20-minute bus ride away from me and were gracious enough to lend me their very beautifully-crafted, ~$649 uCraft (Y) USB cable for a month.
Part 2: KINGREX uCraft (Y) USB Cable
The split-Y design of the uCraft cable complemented the iUSBPower perfectly. AMR iFi actually sells the Gemini cable, which has the same split-Y design that separates power and data leads, but wasn’t available at the time (it’s now fully stocked).
Interestingly, KINGREX actually manufactures its own USB power supply, the UPower — a battery-based design designed in the same form factor as their compact USB DAC, the UD384. However, it was designed with their uCraft and uArt (Y) cables in mind, and thus only contains one USB 5V output and doesn’t provide data pass-through like the iUSBPower.
Personally, I found the iUSBPower more useful for my setup, but buying into a single system could be nice as well. The idea is to connect the uCraft (Y) cable to the computer and to the UPower, while inputting into the UD384, and finally passing the signal into their HQ-1 headphone amplifier — similar to iFi Audio, KINGREX has it thought out when it comes to a product ecosystem.
It was nice to see that KINGREX had the same kind of ideas for power treatment as iFi Audio, though when it comes to build quality, KINGREX takes it up another notch. The uCraft (Y) USB cable is exquisitely built, entirely by hand. The estimate is that a single KINGREX technician can at most build three of these cables a day (usually two), because of the time-consuming process, not only to solder the delicate USB leads, but also to apply the special damping treatment within the cable, and finally to close the metal-crafted end connectors.
Inside, the uCraft sources high-end Japanese cabling (the alternate “Unanimous” series cable from KINGREX, the red-colored uArt, uses wire from an American-made source) in an inverted concentric architecture, similar to the Oyaide NEO d+ USB cables. This wire is additionally cryogenically-treated before assembly to ensure metallurgic structural integrity of the crystal boundaries. Basically, everything about the cable aims to isolate the data from the power leads, and to minimize jitter during a streaming process (USB DACs do not work in packet mode). The layout of the Y cable is not conventional, where the data and power leads are joined together at the very end where the B-plug is, but rather the two leads are conjoined right before at a separate integration box, leading me to surmise that the integration box contains digital isolation chips (like those offered by Texas Instruments).
Upon inserting the USB connectors into the iUSBPower, I could tell that the uCraft was on a different level of fit and finish from other cables. The connectors clicked solidly inside and refused to budge.
So here’s the kicker, and where you suspend disbelief: to me, this cable audibly alters the sound of your system. I was not expecting this to happen — perhaps jitter really was eliminated from the cable (conversely, the alternate theory is that there’s more jitter now, but I prefer not to think of it that way, so just indulge me), but everything about the uCraft cable screamed clarity.
With a Firestone Audio Custom Cute DAC, there was an added sense of transparency and space that I didn’t know was possible. Even without the iUSBPower, things were noticeably cleaner. The only unit I tried that didn’t improve appreciably was again the Resonessence Labs Concero HP. Everything else, whether it be the Miniwatt N4 (reviewed here) or the Micromega MyDAC, seemed to improve in transparency and space. It was hard to reconcile my logic circuits with what I was hearing.
However, the KINGREX uCraft (Y) USB cable is not at all suited for a portable system, or even a small desktop system.
First, it’s far too long. At two meters in length, the cable was never meant for a tiny DAC the size of a Gideon’s International bible. It was meant for grand systems — dCS ring DACs, massive monoblocks, and ribbon speakers. Even if KINGREX made a shorty version of this cable, it’d be too stiff and non-compliant to carry around. There is a substantial amount of damping and insulation material shrouding its cryogenically-treated raw wire. A two meter run across a wealthy audiophile’s listening room is perfectly reasonable for the uCraft, but highly unwieldy even with a Micromega MyDAC, a Firestone Audio Tobby, or a Wyred4Sound μDAC2-HD — never mind my tiny iBasso D7 or the Resonessence Labs Concero HP.
The ergonomic disadvantages of the uCraft are not a knock on KINGREX, however. Clearly, they were thinking of bigger things than the portable segment when they designed the ‘Unanimous’ series — like its name fortells, this is more of a no-holds-barred type of endeavor.
So yes, the uCraft (Y) cable is not cheap (mind you, prior to receiving it, I had no idea that the cable was $$$ — I just knew it was nice)— it’s nearly three times the price of the iUSBPower itself, not very pliable, and a bit too long for a desktop setup. However, along with the iUSBPower, what I was getting was the best of both worlds — one painstakingly hand-built boutique cable, and one precisely regulated power supply. On top of the reverse osmosis and activated carbon, these were the galvanically-coated pipes! In the pursuit of good coffee, one can never skimp on the water source (or so I rationalize).
A very special thanks goes out to Miss Carol Tseng at KINGREX for allowing CYMBACAVUM to use the cable for an extended period of time, and for letting me take a peek inside the impeccable KINGREX listening room.
Special thanks also goes out to Vincent Luke at iFi Audio for his immense help in understanding the iFi origin story and for his impeccable professionalism.
Mr. T is an in-ear fanatic by day, and writes SOAP notes by night.
He pities the fool who actually has the patience to read through his stuff.
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