Technique for editing interleaved digital audio data

Abstract

In producing an edited tape (31) the lead-in material up to a first edit point is separated from the lead-out material running from a second edit point by a space containing unwanted material and accommodating the actual or notional splice. The unwanted material ensures correct operation of error protection for all of the wanted material on replay. The first and second edit points are marked by codes placed on the tape (31) by a code processor (43) and supplementary head (42). During replay the digital data recovered from the tape by a head (32) is entered into a random access buffer store (34) under control of a write address generator (38) and read out to output electronics (37) under control of a read address generator (39) running at the audio sampling rate. The write address generator (38) normally runs at a rate corresponding to tape speed but the code processor detects the codes for first and second edit points and a control unit (51) stops the write address generator (38) between such points so as to discard the unwanted material. The store is then replenished by speeding up the tape by a comparator (40) and speed control unit (10) in an arrangement which preserves a constant relationship between the read and write addresses, i.e. a constant degree of filling of the memory (34).