Audio Devices was a quality American brand of reel to reel tapes in the 1950s through the 1970s. Their tapes were often used for professional recordings in the 1950s and 1960s and had a great reputation – equal to Scotch in the early days. In 1972 they were purchased by Capitol Records. In general, they kept up with the market in terms of quality, and the performance of their standard tapes in basically equivalent to Scotch, Ampex, Soundcraft and others through the early 1970s and before the Japanese tapes came into the market. They also released a low noise formulation, and later a low noise / high output tape. Their final tape, released under the Capitol brand, was called “The Music Tape” and was equivalent to the best back-coated tapes of the time like the Scotch 207. Except for the Q15 tape, all tapes made by Audio Devices have help up well and recommended to be used today, except for the tapes with Acetate backing.
From the beginning, Audio Devices had a comprehensive numbering system that included the tape length and formula code. The first 1 or 2 digits stand for the length (6-600 ft, 6-900ft, 12-1200ft, etc.) and the last two for the formula code:
51 – Standard (Type 1) tape, SP (standard play), 1.5 mil Acetate backing
51M – Standard (Type 1) tape, SP (standard play) , 1.5 mil Acetate backing, Low Print for Master Recordings
57 – Low Noise (Type 2) tape, SP, (standard play) 1.5 mil Acetate backing
71 – Standard (Type 1) tape, SP (standard play) , 1.5 mil Polyester backing
71M – Standard (Type 1) tape, SP (standard play) , 1.5 mil Polyester backing, Low Print for Master Recordings
77 – Low Noise (Type 2) tape, SP, (standard play) 1.5 mil Polyester backing
41 – Standard (Type 1) tape, LP (long play), 1.0 mil Acetate backing
61 – Standard (Type 1) tape, LP, (long play) 1.0 mil Polyester backing
67 – Low Noise (Type 2) tape, LP, (long play) 1.0 mil Polyester backing
31 – Standard (Type 1) tape , DP, (double play), 0.5 mil Polyester backing
31T – Standard (Type 1) tape , DP, (double play), 0.5 mil Polyester backing, tensilized for greater strength, later this was made standard for DP and TP tapes.
33T – Low Output (Type 2A) tape, TP, (triple play), 0.5 mil Polyester backing, tensilized for greater strength
Later, the tapes were re-branded as “Capitol 2” and they changed the numbers somewhat, and the formulas were similar (although there were no longer Acetate versions):
72 – High Performance standard (Type 1) tape, SP (standard play) , 1.5 mil Polyester backing
79 – Low Noise (Type 2) tape, SP, (standard play) 1.5 mil Polyester backing
62 – High Performance standard (Type 1) tape, LP, (long play) 1.0 mil Polyester backing
69 – Low Noise (Type 2) tape, LP, (long play) 1.0 mil Polyester backing
32T – High Performance standard (Type 1) tape, DP, (double play), 0.5 mil Polyester backing, tensilized for greater strength
Notes on other formulations:
The Capitol “High Performance” tapes, sold without a formula number, were repackaged standard (type 1) tapes that came out after the Capitol 2 tapes. Similarly, the Capitol “Beautiful Box” tapes were filled with tapes that were either brown (standard-type 1) or gray (low noise-type 2), depending on when you bought them.
The FDS Series is their Type 3 Low Noise / High Output tape with backcoating, simply named “FDS” with the tape length. It was available in SP and LP thicknesses, in 7″ and 10.5″ reels.
All of these tapes were made to a high quality standard, and all of the tapes listed can be used today. They do not suffer form sticky shed or SBS, and have a low shedding index.
