Back in 1972, Billboard magazine published an interesting retrospective on magnetic tape.
One of the more interesting articles states that Audio Devices laid claim to the first computer tape in 1957: https://shorturl.at/hqGS8 Apparently there was a patent fight over Marvin Camras' tape patent, with 3M losing the case in 1955. I've processed quite a bit of 60's Audio Devices tape. Good stuff--generally very reliable even after more than 50 years. One problem with a lot of the old reels is that the paper manufacturer's labels have long been lost, due to the adhesive drying out. AD tapes of the period are quite recognizable because legends like "AUDIO DEVICES COMPUTER TAPE" are molded into the reel flange. --Chuck
