Putting the ding in fun? Again, hifi advances like the miniaturization of existing tech, novel production methods, new parts, performance increases etc rely on research and development. R&D funding for the military, medical, industrial and IT sectors massively trounces what even the largest audio conglomerates can allocate, what to say of small boutique firms. Hifi electronics rely on opamps, FPGA/DAC chips and transistors developed for these busier sectors. They benefit from ongoing advances outside our small cottage industry which can't afford to fund them. Meanwhile high-end's drive units are limited to mostly hifi speakers. Pro and sound reinforcement units are for concert venues, clubs, churches and public address systems. As high-volume special-application parts, the automotive industry has its own catalogues and key suppliers. As we learnt from a recent KR Audio announcement, about a range of new tubes financed by big order commitments from LampizatOr and a UK-based e-commerce vendor, parts manufacturers can fund improvements with sizeable orders. Those of course tend to be very unlikely from new small companies whose operating capital is generated exclusively by sales. In their case, true custom orders—substantially more than just minor modifications to stock parts—only come after many years of successful business. Neither Jim Thiel nor Richard Vandersteen started out using their own drivers.


Æquo Audio did from day one. Already their first product sported ground-up drivers not found elsewhere. The Ensis midrange inherited by Stilla combines a continuous mineral-loaded self-damped polypropylene cone without dust cap with an Accuton-style very fast symmetrical motor system. Like Ensis, this central driver is only low-passed on top with a 6dB/1st-order filter at ~2'000Hz. The lower roll-off mirroring the woofers which enter with a 2nd-order/100Hz low-pass is purely mechanical. This avoids the usual 3-way's midrange high-pass, making Stilla more of a 2-way plus precision-matched active sub in one svelte cabinet. About the bass system which uses purely analog compensation to measurably mimic the behaviour of closed-box loading, Ivo explained that "Stilla wouldn't have been possible with the woofer tech of just 5 years ago." Their 7-inchers benefit from the latest advances of mating a long-throw cone to an ultra-fast motor system.


Æquo's new soft-dome tweeter for Stilla sports the same optimized airflow magnetics of the Ensis tweeter, then advances wave guide efficiency to increase lateral dispersion whilst limiting floor and ceiling reflections. To fully control their cabinetry, production of thermo-formed synthetic stone was already in-house for Ensis and developed further for Stilla. It starts with sourcing sheets of raw material whose thermal specs and tolerances exceed Corian and Hi-Macs and which contains 70% ceramics. It heats them at just the right temperature before a 20-ton press bends them into the desired shapes in precision moulds. This process R&D and related industrial equipment relied on the two principals' savings from previous jobs before the first Ensis ever sold. Later another smaller round of funding involved all team members and some of their families. This maintains 100% in-house ownership and prevents putting any ding in fun-ding.


Relative to driver research, Æquo told me of a very substantial personal data base not only of existing units they've tested but of individual suppliers they've identified from which various major driver design houses source their specific materials. This allows Ivo to strategically specify what exactly he wants for his transducers. Such detailed knowledge makes him an unusually active collaborator with his driver manufacturers.


Relative to cabinet design, Ivo is adamant about time alignment to support a flawless step response. Much development time is spent also on resonance optimization. This led to research into the optimal thickness of the Ply and synthetic stone skins of Stilla's 'boat hull' and specialty glues which bond them to double as constrained-layer damping compound.


For Stilla, high-power music testing past the original plinth design of aluminium with synthetic stone inlay led to a revision. This increased the plinth's mass via added thickness to make this structure even more effective at sinking remaining front/aft cabinet resonances to ground - vital for clarity under stress like massive symphonic music at high SPL. No matter what aspects of Stilla's design I inquired about, Ivo had very detailed lengthy explanations about their respective why/how to demonstrate an unusually comprehensive approach to speaker design. Much effort was spent to reduce this speaker's physical dimensions yet guarantee full-range performance without typical compromises.


Those perfectly happy with big imposing speakers dominating their living-room decor won't appreciate that aspect of Æquo's efforts. In fact, they may write off Stilla precisely because of her petite figure. That's not the target audience. The target audience are those who want big high-end sound in a compact package and not add a third or forth box called a subwoofer or two. They fully understand that physical miniaturization without sonic shrinkage is a rather costlier proposition than inconsiderate design laziness which advocates grotesque sizes; plus one which categorically relies on active bass that's adjustable to adapt to various rooms. Those who have conceptual issues with self-powered bass systems or class D for sub 100Hz coverage won't be compadre with Æquo's approach. They will have to wait for their forthcoming €10'000/pr passive model.


On raw Stilla specs, we get dimensions of 107x16x26cm HxWxD with a weight of 20kg/ea. 2.83V sensitivity is 90dB and claimed bandwidth 18Hz-35'000Hz. Impedance is a nominal 8Ω to "make her compatible with a wide range of excellent-sounding amplifiers of lesser power". The materials palette is synthetic stone, Plywood and billet aluminium. The connectors are WBT binding posts for the speaker cable and SpeakOn for the 3-metre power cord. The analog adjustments on top of the speaker are for room size [XXS to XXL] and placement [boundary compensation). The manual adjustment is for the cabinet tilt via single wheel. The standard finish is matte white. High-gloss black and various wood veneers occupy the first surcharge tier, custom RAL colours the second.
... to be continued in mid April...

Æquo Audio website