Reviewer: Joël Chevassus
Financial interests: click here
Source: Esoteric K-03, Lumin S1, Apple iMac Yosemite/Audirvana, Trends UD-10.1, MacBook Yosemite with HiFace USB bridge
Amp/Preamp: Coincident Technology Statement Line preamplifier, SPL Volume2, Luxman M-800a x 2 (bridged), Trends TA-10.2]
Speakers: Magnepan 20.7 [on loan], Vivid  Audio Giya G1
Cables: Skywire Audio 2020 digital cable, Naturelle Audio interconnects Live 8 MK2, Grimm Audio TPM interconnects, High Fidelity CT1 Enhanced speakers, Triode Wire Labs interconnects[on loan]
Power Cords:  Supra, DIY, Triode Wire Labs 10+
Stands & room: Music Tools Alicia furniture, DAAD 4 bass traps, Microsorber room insulation, PYT Panels
Review components retail: ca. €32'000/pr for the speakers, €6'000/ea. per subwoofer


World premiere
. Nowadays design unconventionality has nearly become par for the course. Our consumer society so addicted to constantly new electronic gizmos has raised the need to distinguish oneself vis-à-vis the norm. The most obvious example is Cupertino's hi-tech company which keeps reinventing modernist design to enjoy massive global sales. But audacious industrial designs have not always met with success from a sales and marketing perspective. Taking pride of place in a Modern Museum of Art doesn't equate to profitable sales after all. Yet the French have been quite talented at finding new ways to stand apart from the common approach. Their pride and desire to shine as the Sun King's heirs has even pushed them to promote the so-called la French Touch.


And indeed, there are plenty of clever ambitious design works in French history which have met more or less successful ends. Just think of the classic Citroën DS or the so-called Duck. In the small corner of our audio industry too, there are many references to this Gallic genius. From the Cabasse La Sphere to Audionec's Answer to Devialet's Phantom, many French entrepreneurs have made unique proposals. Even so, the by far most outrageous Gallic loudspeaker contribution must be the one from Gilles Milot. If you consider Cabasse's or Devialet's examples unusual already, perhaps Gilles Milot's is an irregular UFO migrant emerging directly from the cadre of Men in Black extras. Whereas Jean-Michel Jarre and Philippe Starck provide the mass market with low-fi urban and geeky designs, Milot for more than 30 years already has explored the seemingly most improbable back roads to high fidelity. Despite his brand not enjoying the renown and mass awareness of big French players like Focal, Cabasse or Triangle, Gilles Milot has contributed very actively to the development of the French audio industry. By most of its members, he is in fact highly respected as undoubtedly the most inventive French man to work in the field of audio transducers today. Indeed Mr. Milot is anything but a rookie. He has already lived several audio life times before his most recent achievement in the Acoustical Beauty company.


Our gifted French engineer started his personal audio crusade for innovating better sound in the early 70s. In 1974, he founded the Audience company in partnership with Yves Bernard André, founder of YBA. By 1976, Milot launched the Leedh brand (that means Holophonic Laboratory of Research and Development) with Michel Reverchon of Goldmund. Under Leedh, he released several loudspeakers like the Perspective, Theoreme, Aura, Starlet, Elfe and Ether. This paralleled extensive research into unusual materials like concrete plaster, silicone grease or cochineal extract for fiberglass membrane treatments. From 1989-2006, Milot worked for Harman/France as R&D director of Audax, the famous French loudspeaker manufacturer where he pioneered new membranes and drivers like Aerogel or the HD3P.  And he continued to release further speaker designs such as the Leedh Psyche, Nazca and Ica.


But Gilles Milot was not solely focused on transducers. In 1980 he founded Micromega whose goal was to market electronics designed by Leedh. This company he sold to Daniel Schär a few years later. In 1984, Micromega were first to release a CD player in separate transport and converter chassis. The cooperation between Micromega and Leedh lasted until 1988. Having enjoyed numerous discussions with Milot, I think of him as one of the very few who is this deeply and extensively involved with technical audio developments in any number of applications. Perhaps only someone like Nelson Pass spends equal time (which is to say, day and night), to push new developments.


From the beginning, Milot was convinced that the holophonic speaker would be the way forward to acoustic holography and hifi heaven. The main principle of the so-called holophonic speaker is the strategic use of multiple sound sources to create a quite perfect hologram. By 2007, he founded Acoustical Beauty to promote and integrate these emerging technologies into a new range of speakers. A year later, the French Ministry of Higher Education and Research recognized Acoustical Beauty as the winner of the national competition for the Creation of Innovative Technologies.  Acoustical Beauty had designed a unique and completely different speaker from anything that came before. This came to market as the Leedh C and later the Leedh E. in Leedh's current catalogue, the state of the art in holophonic electrodynamic speaker remains the Leedh E2. It's a speaker without a box where each driver is instead housed inside its own pod. All previous Leedh C and Leedh E versions are upgradeable to the current incarnation.


The Leedh E2 relies on the unique Acoustical Beauty drivers (ABD or HPAB in French for Haut Parleur Acoustical Beauty) which operate in just 0.3 litres of sealed space. Ironless motors with a ferrofluid suspension reduce harmonic distortion as well as parasitic resonance modes of the diaphragm, basket and trapped air. These radical HPAB drivers contain no soft iron pole piece, no foam/rubber surround or even spider, all of which, according to their designer, account for the majority of mechanical defects in more conventional driver designs. Each driver motor combines 18 magnets to immerse the carbon/epoxy diaphragm's coil in a constant magnetic field during up to ±7mm excursions. With 660g of rare earth magnets per driver, the total magnetic mass for a pair of Leedh E2 equals 8kg. The ferrofluid fills the entire volume between the motor's cylindrical enclosure and the diaphragm's tube, with the fluid held in place by the magnetic field. Its function is to create an anti-resonant structure and control the radiation directivity.


Our multi-pod UFO's external architecture is as follows. 20Hz-100Hz is covered by two horizontally opposed identical modules at the speaker's base oriented to fire sideways. Building up from 20Hz-1'000Hz, another such twin module sits at ear height also firing sideways. Finally 20Hz-7kHz goes to a third twin module whose active driver aims forward and the passive radiator backward. The latter cancels internal pod resonances. Finally a dedicated front-firing tweeter pod covers 7kHz-20kHz. Carbon/epoxy tubes connect these modules to the plinth. This minimum-baffle array with controlled radiation pattern is naturally minimalist and its physical 'dematerialization' supports easy domestic integration. Finish quality presents the base materials in their natural forms to avoid ostentatious luxury. Thus maximum budget is applied to acoustic not optic features. To learn more about the drivers, the website describes them as pistonic devices of 54mm diameter wherein a tube sliding in a ferrofluid sleeve is closed at one end by a carbon/epoxy cone.


To move its resonance mode to the highest possible frequency and net the greatest uncoloured bandwidth, mass had to be the lowest possible yet rigidity extreme. These mutually exclusive demands arrived at the carbon/epoxy composite for its very high Young modulus as exploited for space exploration; and geometric optimization via vibro-acoustic simulation software and suitable reinforcement from a short rectangular coil. This diaphragm's first torsional mode is postponed until 1.5kHz. Its primary bending mode doesn't occur until 14kHz.  Across its useable bandwidth of 20Hz–7kHz, it encounters only 5 modes. Contrast that to a typical mid/woofer whose first mode appears at 60Hz, to be followed by another 100 across its useful bandwidth. Each mode represents artificial reverb, coloration and distortion to add up to significant distortion across the pass band. Milot's cone is concave to control bandwidth and reduce residual deformations.