The Evolution of Audio Technology By ADANIELLY 1876 Bell's "Liquid Transmitter" 1880 78 RPM Shellac Disc 1902 Western Electric Type 22 1906 AM Radio 1946 1st Mobile Phone Service 1949 7" 45 RPM 1963 Compact Cassette 1964 8-track 1982 Compact Disc 1992 Mini Disc 2001 Satellite Radio 2001 iPod 2002 HD Radio 2007 Iphone 2013 iPhone 5 2020 iPhone 12
