As touched on earlier, planarmagnetics seem to have sucked up most the headphone space's oxygen. Is it easier to design a thin-film driver from scratch than a classic dynamic? Is public perception soft on pistonic diaphragms—20th century's tech? Whatever the correct answer, from my more remote seat I don't often come across new dynamic models with serious ambitions. Now that I presently have with aune's AR9000, this very mature tech clearly still has lots to give. It may lack exotic status but between its diaphragm and ear removes the airflow obstruction of stave magnets which balanced-drive planars insert. When those work like drum skins excited by signal voltage not mallets, I always wonder how prolonged use doesn't stretch them out. Unlike drum skins which get retightened to maintain their pitch, planar diaphragms have no adjustments. Unlike the AR9000's super-stiff carbon-fibre sandwich cone, thin-film membranes would seem prone to flex and ripple. Unlike planars which move very little to not hit their magnets, a dynamic driver's suspension allows far higher excursions. The driver can be far smaller yet still move more air. Our ear-canal aperture averages 7mm across. A planar driver of 95x86mm is vastly larger. This has most its emissions miss and reflect off us—rather ineffective. All things considered, perhaps dynamic headphones aren't as antiquated as the planar renaissance could suggest? Wearing 'n' hearing this aune did trigger such musings to look up history. In 1921 Edward Kellogg and Chester Rice developed the first working prototype of a moving-coil speaker cone for General Electric in Schenectady, New York. Its patent filed in 1924. By 1926, RCA released it commercially as the Radiola Model 104. In impressive fashion, the AR9000 seems to say, "Happy 100th dynamic birthday!" Meanwhile AI credits Jim Winey of Magnepan as creating the world's first planarmagnetic speaker driver in 1969. By 1972 Wharfedale adapted it to headphone use shortly followed by Yamaha's 'orthodynamic' models. If wisdom comes with age and experience, the dynamic driver would seem to pack rather more. End of detour.

… to be continued…