Audio Tape Specifications - Studio Tape Formats

Studio Tape Formats

As well as ¼" tape, studio and multitrack machines use tape widths of ½", 1" and 2", and at least one 3" machine was available for a time. There is also a 35 mm width.

Tapes of ½", 1" and 2" width are available in many professional formulations, especially but not only formulations of 35 µm thickness (the thickness known as long play when used as ¼" tape). The wider tape also made it possible to produce professional quality tapes of about 25 µm thickness (the thickness known as double play in ¼" applications) in ½" and wider formats.

In all tape widths including ¼", some studio machines use one-sided platters instead of reels. As normal studio practice is not to rewind immediately after recording or playing but rather to store tape with the start end in to take advantage of the even tension produced by the tape transport, tapes from these machines were generally stored on the platters even if the machine was capable of mounting an NAB reel. Other machines used NAB or custom reels in the larger width.

The sizes of platters and their hubs varies, NAB hubs being most common, and tape lengths up to 5000' not uncommon.