tapes, will cause the listener to forget the difference in backgrounds and accept the sequence as perfectly
natural. The intervening noise has shocked the hearing system into forgetting temporarily everything
before the shocking noise, so he does not notice a background change at all.
In utilizing any of these techniques, do not consider the job well done unless the sequence can be
listened to critically without noticing the transition. It must sound natural--as if it happened that way.
An imaginative editor, for example, in joining heavy applause to a following voice in a persistence
blend, might cut part way into the first following word, on the assumption that if the sequence had
actually happened the way it was edited, part of the first word would have been drowned out by the
Effects of editing too closely. When different sounds are spliced too closely together, a third
sound will be heard which may be a puzzle. It may be caused partly by transient vibrations in the
physical ear, partly by hearing persistence, and partly by lack of recognition time. In any event, this
garbled sound can always be eliminated by the insertion, at the splice, of a minimum of 1/60th of a
second of tape from the same background of either of the two tape segments spliced together. If a
person gets into the habit of saying the portion to be edited, the inserting operation to remove a third
sound will not be necessary.
Program timing. Timing of tapes may be important before duplicating. It may be necessary for
a program to last an exact amount of time. Sometimes, this means that more program time should be
added or time subtracted. The method for doing this is to start by timing the original tape. Decide
which areas are to be eliminated and subtract them from the total. Exact timing can be achieved by
fadeouts at opportune moments, addition of narration; and by using themes or sound effects as fillers.
a. Timing tape may be used to insert exact pauses of time.
b. To use this timing tape, determine the length of pause needed. Use the markings on the
timing tape to cut the tape at the desired time. Insert by splicing into the sound.