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Nano is the new cryo. When cryogenic treatment of cables first made the hifi rounds, it was mocked as voodoo. To protect their honor, a few manufacturers initially chose to call it 'proprietary treatment'. As the years passed the efficacy of hifi cryo on wires and even tubes became more widely accepted. Audiophiles began to understand that this process had a successful application history with car and tractor engines, guns, musical instruments, space craft and many other metal-working industries well before hifi discovered it.


Of late our little industry has been invaded by nano. The brochure for Avantgarde Acoustic's Duo Primo is one example. "The Kevlar midrange cone of the M2 Omega is coated with trillions of tiny micro fibers generating a 'Velours Damping Effect'. This incrementally small fur of the VDE technology cone effectively reduces partial resonances of the cone itself. Furthermore the microscopic fibres of the VDE technology help to effectively absorb high-frequency distortions."


Joseph Szall of ATD is the designer of the driver made commercially famous in the original Magico Mini and since seen in speakers by Expolinear, Volent and Cappricio Continuum: "Having played a lot with 'hi-tech' honeycomb composite structures and in general with composite cones—Kevlar, Carbon fiber, Dyneema—I was always nostalgic for the sound quality and performance of the original Zellaton cones. I collaborated on a few projects with Jürgen Görlich who, having taken over manufacturing from his uncle Dr. Podszus in the 60s, produced Zellaton cones continuously until the end of the 20th century. For my new developments I used a syntactic foam of aerospace derivation formulated such as to have a different density along the depth of the cone (smaller cells near the outer skins and bigger ones at the center of the core). The very special skins are state of the art for this application. They consist of nano-graphite fibers in a 3D alea-structure matrix (Hypergraph) strengthened with vacuum/plasma Titanium surfaces. Thus was born the Ariacell GTi = Z3."

In my interview with Zu Audio's Sean Casey on their Dominance flagship, he explained that "... the nano materials and application processes reduce weight, increase strength and propagation velocity of the drivers without incurring any sacrifices in damping. In 2004 we began to experiment with cutting-edge DuPont nanotech-engineered coatings and solids. The initial reasons were to realize the best possible gloss finish which would also be far tougher. These nanotech-engineered liquid solid ceramics, fibers and synthetic resins performed as promised. We quickly recognized the benefits and made the switch. It was during this process that we also got into experimenting with applications for loudspeaker cones and diaphragms. While we had extensively tested coatings, microspheres and binders on driver cones over the years, this new nano material presented a novel set of attributes and opportunities for our widebander platform.


"Nanotech for cone materials, layups, binder additives and formulae, tubes, spheres, coatings, infusions etc. make for an exciting time to be a paper driver. Then we got sidetracked from the liquid solids and invested time again in a whole new range of satellite-grade graphite matrixes. After a few years of on/off experiments with these exotic layups, we returned to nano materials and liquid solids to start treating the paper with various micro materials for even more vibrant and detailed tone. Today we impregnate the paper pulp post pressing with a liquid solid matrix utilizing several nano-processed materials. Some key components and compounds include nanosphere ceramic balloons, melamine, synthetic epoxy A/B, cristobalite, amorphous fumed silica and aircraft dope.


"We continued to watch and occasionally experiment with new fibers and mats. They are still very promising, especially what's being done with buckypaper. For us however a tone promising pulp-free combination of these new materials has not yet been identified. Nothing has proven to be as well behaved as natural fibers. There’s just something about paper. Its balance of strength, propagation velocity and damping all contribute to that tone and fidelity we pursue. But add the right combination of old coating technologies plus nano materials and adhesives and fortuitously paper maintains its vintage advantages well into the 21st century. Currently the Dominance is the only Zu speaker to benefit from these nano-endowed drivers."

Nanofied. Nanotized. Though it's a du-jour N-word phenom that might ring hollow, closer investigation reveals a plethora of man-made micro materials like hollow spheres used in polymer additives, tiny fibers and tubes from the chemical industries like DuPont which to the naked eye might look like nothing more than Talcum powder. Yet via impregnation of porous materials, as surface applications in binders, as glue stiffeners and similar, nano particles can strengthen loudspeaker diaphragms or alter their molecular surface texture to attenuate or scatter surface air turbulence. Just mentioning nano in one's marketing materials to seem cutting edge isn't specific or necessarily factual. But this doesn't mean all such mentions are empty or point at the same.


In toto, there's a very real chance that once again advances in a hi-tech sector outside audio can benefit our passion as our manufacturers learn how to best take advantage. On surface finishing for example Wikipedia tell us about "a broad range of industrial processes that alter the surface of a manufactured item to achieve a certain property. Finishing processes may be employed to improve appearance; adhesion or wettability; solderability; resistance to corrosion, tarnish, wear; hardness; modify electrical conductivity; remove burrs and other surface flaws; and control surface friction." Particularly loudspeaker drive units would seem to be prime candidates awaiting sanctification by Uncle Nano. I expect that just like cryo this could in fact become ubiquitous for hifi in a few years' time...