the original 1967 signature was "crossbeat", a 30-second electronic music piece sourced from the bbc, composed and realised by david cain of the bbc radiophonic workshop. the current themes for both "am" and "pm" are two of the most recognisable in australia. the two themes, composed by tony ansell (who composed many themes for the abc news and current affairs department in the 1980s), were based on a similar theme and performed in a similar manner on a synthesiser using a brass-type patch. the similarity between the themes represents a significant link between the sister programmes.