ESB HB 1.10S4 Sub 10 Inch Car Subwoofer Harmony Series 200w RMS 4 OhmHB 1. 10S4 10" 250 mm Subwoofer The Harmony brand was launched in the 1980s, together with the first home loudspeakers produced by ESB. The production of Harmony car speakers began in the 90s, with a wide range of products that combined high quality performance at a lower price than the ESB speakers themselves, yet without ever forgetting the final goal high fidelity speaker capable of reproducing the entire sound spectrum. This year, Harmony returns