Notable Japanese Speakers

In June of 1955, Mitsubishi Electric introduced a monitor speaker for high-fidelity broadcasting. It received critical acclaim in a comparison among famous Japanese and overseas speakers conducted by NHK Science & Technical Research Laboratories. In 1958, the R-305 type was formally adopted as NHK's standard monitor. The same year, a new anechoic chamber was completed and audio research further progressed with the adoption of a variety of new measuring instruments. Also in 1958, the P-610 and 2S-305 types were completed. Both models would become notable products in the history of Japanese speakers. Conventional speakers used iron as the pole material in the magnetic circuit, but Mitsubishi Electric succeeded in replacing it with iron cobalt in joint research with Mitsubishi Steel Mfg. Co. Ltd. When iron cobalt was adopted in the 2S-305 type tweeter, performance improved even further.