The keys to ATH-ANC23’s performance are the speakers Audio-Technica chose for the earbuds, and a battery-powered in-line active noise-cancelling box that sits roughly half way between the buds and the L-shaped, highly case- and device-compatible 3.5mm headphone plug at the bottom of the black cable. Powered by a single AAA battery, the active noise cancellation box has a shirt clip on the back, plus an on-off switch on the side to activate two…
