Much has changed, though, in the course of driver development. First, the APERIO diaphragm now uses a complex multilayer film comprised of outer layers of 7µm-thick BOPP (bi-axially oriented polypropylene) that enclose and protect a thin 24 Kt gold inner layer held in place by an acrylic adhesive. Next, the new double-sided driver uses a fascinating sandwich-like structure featuring extremely rigid glass-filled polypropylene sulfide outer frames. Working from the outside in, the next layers in the ‘sandwich’ include outer gaskets, followed by gold-plated OFHC stators, polypropylene spacers, and—at the centre of the structure—the multilayer gold diaphragm. Warwick Acoustics has created an automated, high-precision diaphragm tensioning system that ensures tensioning consistency to “within a fraction of a Newton” and that, says Warwick Acoustics, ensures diaphragm tension is “differentially equalized in all axes across the film surface.”
The APERIO headphone ear cups are, as in the Sonoma M1, made of light, rigid injection-moulded magnesium, while ear cushions feature a combination of open and closed-cell foam interiors with smooth Cabretta leather outer surfaces, perforated Cabretta leather touch surfaces, and an open-weave fabric on the inner ring surrounding the ear. The headphone’s weight is a very reasonable 405 grams and Warwick Acoustics has lavished great care on its overall fit, finish, electrical integrity, and especially on ergonomics (most notably, on clamping pressures).
I ran the APERIO system with an AURALiC ARIES wireless bridge linked to a music library containing a mix of CD-quality, and high-res PCM, DSD, and DXD music material. The simple result was one of the most breath-taking headphone listening experiences I have ever enjoyed—one that in some respects was like listening to a Sonoma M1 system that had been working out in a gym, taken martial art classes, and worked to earn advanced degrees in particle physics and music philosophy. In other words, the APERIO can do everything the Sonoma M1 system could do and more, and do it with competence, sonic athleticism, depth, and refinement.
The system’s voicing comes as close to the ideal of neutrality as anything I have ever heard (including some exceedingly expensive speaker-based systems). Extension at high and low frequency extremes is exemplary, with the APERIO showing much stronger capabilities than the Sonoma M1 system on loud, low frequency passages and on fast-rising bass transient sounds. For example, I noted that the APERIO handled the mysterious, evocative, and high-amplitude low frequency sections of Nils Frahm’s ‘Chant’ [Solo, Erased Tapes, 16/44.1] with equal parts of power, clarity, and grace.
Resolution, transient accuracy, and almost blinding tonal purity are three of the APERIO’s strengths. On Hilary Hahn’s’ performance on the first movement from the Meyer Violin Concerto [DGG, 16/44.1] the APERIO beautifully revealed Hahn’s amazing fingering dexterity and bowing technique along and her distinctive string tone, which combines elements of sweetness, incisiveness, and—above all—clarity of musical intent. And there it is: the APERIO is about more than sound quality, per se, but about uncovering the very human emotions and communicative intentions underlying the sound.
Dynamic swagger and agility? Most definitely. Put on ‘Tom Sawyer’ from Rush’s Moving Pictures [Mercury, 16/44.1] and note how the APERIO renders the ultra-crisp and super-punchy attack of the late, much-lamented Neil Peart’s drums, the aggressive yet well-controlled and richly textured snarl of Geddy Lee’s bass, or the live-wire intensity of Alex Lifeson’s guitar lines. There is vigour and energy everywhere, but also subtlety and—after a fashion—delicacy shown in the masterful way the musicians modulate dynamics to create dramatic mini-crescendos and decrescendos throughout the song. The APERIO can handle high-energy rock music and other forms of power music with a dynamic athleticism that the Sonoma system could never have matched. Quite honestly the APERIO system can play (much) louder than I personally can bear to listen—meaning one will never complain of the APERIO ‘running out of steam’.
Spaciousness and soundstaging? Oh my, yes. I got a glimpse of what APERIO could do when I put on an old and well-loved audio chestnut: namely, the title track from Andreas Vollenweider’s Caverna Magica [Savoy, 16/44.1]. ‘Caverna Magica’ has long been famous for the way it produces enchanting 3D soundstages through most audio systems, but through the APERIO system I found there was suddenly not just a little but a lot more magic in the ‘Magica’. In fact, the APERIO took the song’s 3D presentation to a whole new level, creating a huge, resonant, cave-like environment, which Vollenwieder’s sumptuous-sounding harp filled beautifully. My point in this observation is to say that whenever there are useful spatial cues in music, the APERIO will find them and put them to great use.