Audio Magnetics Corporation was founded in 1966 in Gardena, California. Sometime before 1972 (maybe in 1970), the company launched a series of blank audio cassettes. It seems that each of the products (60, 90, 120 minutes) was assigned a different suite of four colors for the stripe pattern. The big type is Filmotype Royal, which appears to be a phototype interpretation of Old Style Expanded, originally released by Barnhart Brothers & Spindler before 1893. The smaller text is set in what looks like Trade Gothic Bold and Bold Condensed.