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Certain frequency and amplitude
considerations necessitate that output signals from records, tapes and
microphones be processed to deliver a signal to deliver a signal to the
amplifier that will accurately reproduce the original sound. This item
performs this processing.
The tape head that precedes the
record head to remove any signal previously recorded on the magnetic
tape. This is done by high frequency alternating current that randomizes
the magnetic patterns on the tape.
White noise created by the
magnetized, randomized, iron oxide particles on magnetic tape. Full tape
erasure cannot be obtained because as the tape passes the head at any
given moment, some randomized magnetized particles are in alignment with
the playback head. The random voltage fluctuation produced by these
particles passing the tape head produce noise. This noise limits how
small a signal's amplitude may be recorded.
Tape heads that produce four
separate tracks. In most machines with these, tracks 1 and 3 are played
while the tape runs forward, and when the tape's direction is reversed,
tracks 2 and 4 may be played. However, a machine may be configured so
that all four tracks are used in the same direction simultaneously.
Inaudible ultra high frequencies
introduced to the tape recordings process to improve the fidelity of
problematic audible frequencies and amplitudes usually masked by tape
noise, an inherent condition of magnetic recording tape.