For a game of potential gotcha, these were my expectations. It had been a while since my AVC flexed magnetic muscle in this rig. Once I realized that Pasithea's variable gain could eliminate an extra box and cable, retain remote volume and only change sonics marginally, I opted for simplicity and called it a good day. Now plain logic dictated that if Lumen's conceptual likeness were to play stand-in for my icOn 4Pro, equally little should change. Given Æ's wild cost multiplier over my AVC though with far coarser attenuation steps if equally absentee switching transients, I obviously hoped for a lot more. I simply had no specific notion what said hopeful should or would consist of. Dynamic expander? Energetic accelerator? Micro magnifier? I felt as clueless as a stick in the mud. Time to listen and change my sticky status. The next photo shows the threesome and how the power supply simply scales down the form factor including the bevelled front window which becomes the IR eye. Like the head unit, the PSU's lateral windows are covered in beech wood whilst teak handles top and bottom. Two orange long cotton-weave cables off it are a power cord and three-pin voltage feed with locking connector for the attenuator's backlighting option and knob motor.

This single-ended version was fitted with 3:2 i/o and no step-up gain option. 

How smooth or clunky that motorized action might be I obviously can't report on¹. I was told that the mechanical resistance of the remote's two buttons is adjustable to a client. For my tastes the supplied sample was set too low. I'd fancy springier action for keener tactile feedback. Suffice to say that Stas' manual build has control over all such minutiae. A possible hint about his sonic imprint comes from knowing that whilst practicing the saxophone in his parental home, he did so in a 1.5×1.5m² closet filled with heavy clothing, door shut to minimize noise leakage. His hearing's neural network thus formed whilst exposed to the SPL and harmonic intensity of a powerful reed instrument plus the percussive speed and incisiveness of the drums. Does that suggest emasculated wispy sonic airs as accompany popular perceptions of passive preamplifiers? Or does it predict that Stas likes things more intense, unfettered and loud instead?
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¹ "I currently order the remote control boards from Switzerland's Elma with long lead times as nobody stocks these notoriously expensive parts and everybody else is content with relays and digital encoders. Because of that the control boards use an outdated motor-controller chip. We are developing a custom remote controller board that will help me avoid these backorder issues." 

Back to my mud-stick questions. Dynamic expander? Energetic accelerator? Micro magnifier? I indisputably had the former two; and by a dead-obvious margin that was frankly transformative. Micro magnifier didn't really apply. On the level generally meant by resolution—small-detail perception within fine separation—the icOn 4Pro and direct feed already operate at very low noise floors so a very high level relative to my ability to process. The Lumen makeover had to do with scale particularly in height and depth; swing potential between quiet and loud; and energetic substance. The words 'increased mass' routinely imply a certain darkness and obscuration. It parallels how punching up an image's black level narrows its range of colour values. There are fewer gradients between dark and light. So can extra tonal saturation steal from contrast, richness diminish modulated nuance. This wasn't that by a long shot. Hence my peculiar word combo 'energetic substance'. The Lumen unleashed clearly more energetic intensity. It simply wasn't the nervy haggard caffeinated sort where transients lead but aren't backed by proper follow-through. That's like an amateur's jab executed from just the elbow. It doesn't connect through the shoulder and hip into the foot then ground. It carries no real power. Lumen instead combined greater substance with more intensity or energy such that it didn't incur the usual shadows of deeper density. If we call my system voiced like Raal 1995's ribbon headphones—which it is to the limits of my means and exposure of suitable hardware—then the Lumen bolted on premium dynamic-headphone attributes without overwriting or diluting the ribbon virtues. Rather than either/or, it accorded both styles equal billing. That made for an unexpected hybrid.

Volume up/down here becomes 'love it' and 'quiet now'. Battery charging by USB-C.

For what it categorically wasn't, take your pick: polite, pale or pinched; weak, wan or whitish; lazy, languorous or limpid; distanced, detached or dark. It produced none of these effects many associate with passive preamps perhaps because they heard poor implementations, mismatched installs or mistrust the concept. Calling it a passive might in fact be the worst insult one could call the Lumen. It throws up a hurdle that now must be obliterated before anything else can happen. Perception rules. If people think us a liar, they'll treat us as one regardless of our most earnest protestations. Being virtually synonymous with 'inactive', 'passive' implies a loss of engagement and volition. We are no longer involved. We might even stop caring. We're a casual observer at best; certainly no longer the engaged participant. Since none of it applied, what to call the Lumen to properly reflect its action and set correct expectations? For a single word which best defines the various facets of its effect, think intensifier. It applies equally to directness and dynamics, scale and substance. All four expressions intensified. Not only did this exceed my expectations—nebulous as they admittedly were—the before/after delta frankly eclipsed all imaginative rhyme and cynical reason. Transformer attenuation is passé clunky vintage tech you say? For the most current smarts we should look at the Leedh algorithm which embeds as code on an IC smaller than a postage stamp? Perhaps. Yet vintage played in a completely different league. Classic multi-tapped cobalt-infused iron wound with varying high-purity silver executed to the nth degree of persnicketiness transformed my game into a higher octave. It's certainly not for the faint of wallet or stubborn of beliefs!