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, AURALiC Vega, Aqua Hifi La Scala MkII, Fore Audio DAISy 1, Apple iPod Classic 160GB (AIFF), Astell& Kern AK100 modified by Red Wine Audio, Cambridge Audio iD100, Pro-Ject Dock Box S Digital, Pure i20, Questyle QP1R
Preamplifier: Nagra Jazz, Esoteric C-03, Vinnie Rossi LIO (AVC module), COS Engineering D1
Power & integrated amplifiers: Pass Labs XA30.8; FirstWatt SIT1, F5, F6, F7; S.A.Lab Blackbird SE; Crayon Audio CFA-1.2; Goldmund Job 225; Gato Audio DIA-250; Aura Note Premier; Wyred4Sound mINT; AURALiC Merak [on loan], Gryphon Diablo 300 [on review]
Loudspeakers: Albedo Audio Aptica; EnigmAcoustics Mythology 1; Sounddeco Sigma 2; soundkaos Wave 40; Boenicke Audio W5se; Zu Audio Submission; German Physiks HRS-120; Eversound Essence; Gryphon Pantheon [on review]
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; Arkana Research XLR/RCA and speaker cables [on loan]; Sablon Audio Petit Corona power cords [on loan], Black Cat Cable Lupo
Power delivery: Vibex Granada/Alhambra on all components, 5m cords to amp/s + sub
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: $385 delivered

After my review of the Firewall AC filters, the firm's Louis Motek decided to dispatch three of their $385/ea. (incl. delivery) USB Firewall Keys. "A word about 'burn-in'. People report large burn-in effects during the first week of use. Please be sensitive to this. You are getting three so it will be possible to use one for a week, then switch in a fresh one and see the difference. You can use one, you can use two (for example, one between computer source and regenerator, another between regenerator and DAC; or two in series between computer source and DAC). You can also use three in series. That gets a bit long but if your source is on a table, that's great. Once we get to four in series, we will have a better solution. It will be a special adapter product to connect four USB Firewall Keys in parallel in a special configuration developed by us. This will provide even better sound than four units in series. We are planning for this adapter to be released in about a month or two."

Of course three of these keys already open the doors to the +$1'000 kingdom. You could get a new DAC for that. But then, home-theatre retailers try to bump you up from 5.1 to 7.2 surround. They want to sell you more speakers. Accessory purveyors promote compound gains to increase your investment across multiple units. It's all perfectly legit time-honoured business practice. And, it's fuel to cynics, cyanide to the feckless. There's even a 5% volume discount incentive for two keys; a 10% savings on four. Moving right along, the what's-inside is glued shut in a nearly black swamp Oak casing. Industrious reverse engineers would have to saw or chisel one open. To save them the trouble, LessLoss very sportingly have these two photos. On how it works, think skin filtering. Again. It's the secret LessLoss sauce. Which gets us to does it work? And by how much? Disclosure time. I have not experimented with the Regen, Schiit or AudioQuest USB cleaner gizmos. Hence no value/potency ranking versus the Key. I did review the Wyred4Sound Remedy. That S/PDIF reclocker worked as advertised, particularly on less snazzy digital sources like iPod docks. But then, I've not played with Wyred's subsequent reclocker dedicated to USB. As such, this report on the LessLoss USB cleaning box must happen in isolation, not against similar competitors. End of small print.

'cept for one more thing. Due to its size, inserting the Firewall Key into a horizontal USB port could obscure the one adjacent to it if too closely spaced; or if your USB cable in the neighbouring slot is too fat. On my iMac's vertically slotted ports, this happened depending on which port the Key occupied. Its USB plug doesn't sit centered between top and bottom. There's more wood on one side than the other. So the Key wouldn't clear the generic USB cable connecting my external DVD drive one slot over. If you have excess USB ports, don't fret. If you're maxed out, check beforehand to insure that a FireWall Key won't bump off one of your other USB devices; or reshuffle one connection to make sure the Key clears another cable with its narrow side, not displaces it with its fat one.

Does skin filtering leave skin in the USB game? On my customary red KingRex double-header cable and for break-in, I used two Keys on the power feed and one on the signal leg. Louis subsequently pointed out* that the latter bypassed his device. Hardware chain linking was my usual iMac/PureMusic set to power-of-2 upsampling --> COS Engineering D1 DAC/preamp --> Pass Labs XA30.8 class A stereo amp --> Sounddeco Sigma 2 speakers. Music choices included Amr Diab's truly haunting Mn Asmaa Allah Al Hosna, twenty short vignettes without percussion dedicated to various Arab names of God to become miniature male versions of Sœur Marie Keyrouz vocal calls to prayer. They also included the Secret Trio's Three of us and finally IndiaLucia 1, a mash-up of Flamenco and Indian ensembles led by Polish guitarist Miguel Czachowski (their follow-up volume two is equally spectacular). Audiophiles who truly put the tunes not machines first should Tidal these three productions for premium samples of eclectic world music you won't hear at hifi shows.

* "The USB Firewall Key is wired such that the two signal connectors circumvent it entirely. The only thing that undergoes our skin filtering is the 5V and ground connection. We investigated this a lot before coming to this conclusion. The reason that some similar USB filtering solutions are less effective is that they filter the signal lines as well as the power lines. When the signal lines are filtered, you weaken the so-called eye pattern or signal fronts of the digital impulses. The result is similar to smearing or loss of clarity whilst at the same time seemingly reducing noise. Our understanding is different. When our skin filtering is applied to just power, we provide the best conditions for the signal lines to be interpreted by the associated electronics. In other words, when power contains information, that information gets carried over to some extent to the signal. That's due to the simple fact that information on the power lines influencing its decision making with regards to the actual signal. In technical terms this is called demodulation.

"There are four types of demodulation: amplitude demodulation, phase or frequency demodulation, amplitude intermodulation and digital clock frequency modulation aka jitter. Here we are mostly concerned with the latter. If you so much as even touch the signal fronts of the actual signal, you are working on the wrong end and introduce a type of constant coloration to the nature of those signal fronts. If, however, you concentrate all your effort at stripping the power lines of any information, then the electronics will have the best conditions to interpret the natural untouched fronts of the signal. It's like going to a concert. Who hears the concert better? The person who sits still and merely listens or the person who listens while at the same time checking email, texting his lawyer, buying and selling stock and reading the latest news stories on both his smart phone and portable tablet? USB has four conductors, two for signal (+ and - balanced) and two for power (5V and ground). Your red USB cable has no connection to the power lines on one of its ends and no connection to the signal lines on the other. So if you are connecting three USB Firewall Keys, you would connect all three to the power USB connector and zero to the data connector."

Control system N°2 became the desktop. Here an HPZ230 work station with JRiver Media Center 20 served local files to the active Eversound (now Feniks Audio) Essence speakers. Those tout a quality Gordon Rankin-designed DAC that's deliberately 24/96 to be driverless The single leash was a short Curious USB cable. Here I keyed more strongly into the skin-filtering effects. Perhaps this came from multi-tasking my PC, with Opera, Photoshop, DreamWeaver, Word and Outlook all open. Did this put a minor or major maloik on pure audio performance? Without the Key, solo and chorus vocals were a bit hashier around the edges; dirtier. Unlike in the big system, not only was this effect more pronounced, serializing up to three units was quantifiable though still easier to do on drier recordings without copious real/artificial reverb to blur the lines. Perhaps the best way to explain the Key action is to consider the multiplicity of music. How much of it actually registers at your ears as such? How much do you focus on lead vocals or instruments instead whilst the rest acts as more or less fill or atmosphere?

The LessLoss wood blocks made it easier to experience all of it weighted equally. This doesn't give preference to the obvious foreground stuff, then downgrades all else as secondary or less. Put different, the USB Key softened the psychological zoom function on the central stuff. On the level of attention, it 'zoomed out' to consider the whole as a simultaneously happening whole. If this description seems directed more at the listener than hard sonic facts, I'd agree. That's how certain changes register. One notices them more as effects on the experiencer. Here rapid A/Bs completely miss. Those only consider sonic values. They don't allow us to notice their impact on us having the experience in the first place. What's required is a process, not content consideration. To me then, the real benefit of these LessLoss boxes wasn't so much better sound per se as it was a more wholesome less piecemeal or partial participation in the music. If that makes sense to you, nothing else needs saying. If you only accept hard sonic 'facts' as proper review commentary—the primitive more treble, less bass etc.—I don't have anything except less hash and grain. On pure quantity, that effect was quite marginal. On quality, it was a more relevant matter.

That falls under more of a gestalt changer. Here the usual audio lingo reaches for words like flow vs. choppiness, organic vs. mechanical. Those still remain far softer terms than a 1.5dB depression in the 80 - 130Hz band. Does that make them any less relevant or descriptive though? As I see it, the upshot for anyone trialing these bog oak minis would be to refrain from quick A/B swaps. Instead allow yourself to sink into the playback experience over longer periods. Then attempt to compare which one feels easier and more natural. This drives measurement freaks crazy. But the simple fact is, we don't listen with scopes. And, the ears of our species don't connect to computers and analytical software code but to minds and hearts which embed in human psychology. That's a different perspective than decibels and THD. It really needs other language to talk about in any meaningful ways. For a harder qualifier in that realm, I'd rate the efficacy of the LessLoss USB Firewall Key as higher than most cable swaps. On a purely sonic level meanwhile, changing cables can net far bigger gains. Those with ears will understand the difference. Those with scopes won't. That's how it can go with devices such as these...

LessLoss website