Audio Tape Recorders (Analogue)

One or more audio tape recorders are essential in the sound control area of any television studio. Typical usage includes introductory, play-out, and background music, spot sound effects, and ‘off-stage’ dialogue.

Types of recorder

Tape machines vary considerably in price, quality and range of facilities. A small cassette machine costs a fraction of the price of a high-quality professional reel-to-reel machine. Cassette machines are cheap, small, and easily handled, and cassettes are rapidly inserted and removed. On the other hand, their quality and background noise (signal-to-noise ratio) cannot equate with the heavier duty reel-to-reel type of machine, although more expensive cassette recorders may be sufficient for some purposes. Cartridge machines are good for jingles and effects.

Unlike simpler tape-recorders, a reel-to-reel machine with separate record and replay heads provides an immediate continual check of recording quality, because the output of the replay head can be fed to the monitoring loudspeaker. (All recordings should, if possible, be made using this facility.)

Desirable operational features

Operational experience has shown various features to be desirable in television studio tape machines including:

● Large (NAB type) spools giving, with standard tape, just over one hour’s playing time at 19 cm/s. Removal of the centres to permit the playing of ‘cine’ spools should be quick and easy.

● Frequency response, wow and flutter characteristics should be well within specifications, and regular routine checks made. Machines get heavy use, and performance can deteriorate.

● The start/run-up time should be ‘instantaneouse ’, if accurately timed effects are to be introduced on cue.

● The stability of modern machines is very good but because the characteristics of different brands of tape vary it is desirable that the record and replay gain, the bias and the equalisation can be adjusted fairly easily, and this means reasonably accessible controls.

● There should be jacks for the headphone monitoring of both the record and replay signals, and it should be possible to have pre-fader listen so that a tape can be ‘cued up’ with the tape machine replay fader (if there is one) faded out.

● It should be easy to edit tape on the machine, i.e. to mark the tape with a suitable pencil at the position of the replay head and to spool with the tape in contact with the replay head.

● Although tape counters operated by the rotation of one of the idler wheels can be affected by tape slip it is still possible for them to be quite accurate (an error of only 1e –2 seconds in half an hour). A good counter display (preferably digital showing hours, minutes and seconds) is an asset.