Before revision: Wireless Specialty Apparatus Co., in partnership with Baldwin Radio Company, set up a manufacturing facility in Utah to fulfill orders.Brandes radio headphones, circa 1920These early headphones used moving iron drivers, with either single-ended or balanced armatures.
After revision: Wireless Specialty Apparatus Co., in partnership with Baldwin Radio Company, set up a manufacturing facility in Utah to fulfill orders.Brandes radio headphones, circa 1920 These early headphones used moving iron drivers, with either single-ended or balanced armatures.