If this were a fairy tale, we'd continue with "and so it came to pass". In fact, I had to consult Final's website to insure that my memory—of the three model's matching sensitivity—didn't play tricks on me. Not. That came as a shocker. To the ears, the X's lead of clarity, dynamics and articulation manifested in all the ways we know of when cheating with higher volume. It really played in a completely different league from the III. Talking points would be directness, control and far twitchier dynamic reflexes. The practical upshot of said twitchiness is that you set the level as you usually do, expecting a plush cruise down the music highway. Suddenly little melodic peaks act like road bumps. They shove your head into the roof and your hand races to the volume knob. That difference, between middle-of-the-road stuff and highlights which peek out from amongst it, was demonstrably larger. It behaved as though some dynamic energy got absorbed or stolen by the lighter 410g plastic casings. By contrast, the heavier 630g cups converted all of it into acoustic sound pressure. That's back at a more efficient energy transfer. For all intents and purposes, that behaved like higher sensitivity.

A direct side effect was the sensation of clearly higher information density. Take an ambient groove which every eight bars adds a percussive element; and does so throughout a very lengthy multi-minutes intro before the melodic theme appears. This stacks layer upon layer upon layer of beats and synth chicanery. The obvious tendency is for the deepest/earliest layers to get obscured soon. By the time the higher instruments segue in, one no longer perceives most of the isolated rhythmic motifs at all. They've locked instead into a pulsating holistic construct. The intended focus is now on the melodic development. There isn't sufficient penetration power to deconstruct all the background stuff back down into its individualized ingredients. On that count—hearing deeper into the mix for fuller vertical insight into simultaneity—the X held on noticeably longer. As a result, I literally heard more discrete things. An easy way to visualize the effect is a pointillist painting. The closer one steps, the more it falls apart into individual flecks of colour. As one steps away, these flecks begin to organize themselves into different groups and shapes. Suddenly, everything snaps into a landscape where people are having a Sunday brunch on blankets in a meadow. With the X, my attention could move up very close for the full deconstructionist effect; move back for the holistic view; or hold on to both at the same time. And that's the very definition of high(er) resolution.

Over the III, the VI's balanced armature acted like the macro zoom most single-driver widebander speakers apply to the presence region. It's a resolution/response imbalance. It's a minor forwardness hence higher informativeness across a predefined window in the upper midrange. As such it's more critical of source material particularly for sibilance and related aspects. Not partial like the VI's, the X's resolution advantage was full bandwidth. Rather than exploit an auxiliary parallel driver across a limited band, the flagship's high-mass solution achieved a similar increase of focus and magnification power but applied it across the entire audible range. Key to that appears to be the mechanical integration of the driver with its metal baffle. It must be this ultra rigid coupling which undermines or cuts off the losses which the less extreme builds suffer by comparison. Of course you'd never know until you compared. If you did, the III really would sound like a typical MDF box and the X like a Vivid Audio Giya.

The obvious proviso in all this is not to expect inter-model gaps at this magnitude when siphoning signal off a portable's 3.5mm jack. With our Questyle QP1R and Soundaware Esther Pro, the same exercise with the stock leash shrinks in scope and distinctiveness. This is where I still think Final undersell themselves by not including a balanced harness with their flagship. Its mere presence would be a suggestive reminder on how that's really the end to which the X should be destined. Also, the three-tone scheme of gold, silver and black acts as a reflexive loudness control. It all too easily suggests Dubai shopping mall bling to be overlooked by those who'd fall in love with its exceptional sound. Knowing better, I don't mind the glitz. It fits AURALiC's amp/stand to perfection. Just so, it can be a perception hurdle; unfortunate and inappropriate but nonetheless real. And that would really be too bad.

After 15 years at the helm of 6moons, acquiring the Sonorous X for personal use was a luxurious but I felt deserved birthday gift to myself. What's more, in the present hardware context it really does act as an ultimate best-case scenario. With it I get to inspect even more fully what's on my music tracks vis-à-vis what changes/diminishes/shifts over the various speaker systems we host. Those must contend with room acoustics interference, dispersion discontinuities, crossover problems and phase shifts. Finally, it helps determine the exact recorded bass balance to set our Zu subwoofer to when we play our smaller speakers. If that sounds like mission accomplished, just so. The X just sent all our other headphones packing...

Final Audio Lab website