 In total, 275 performances of 88 different songs were broadcast, of which 36 songs never appeared on their studio albums.Several of the programmes aired live, but most were recorded days (or occasionally weeks) ahead of the broadcast date.The BBC's studio facilities were not as advanced as those at Abbey Road, offering only monaural recording (no multitracking) and basic overdubbing; few retakes of songs could be attempted owing to time limitations.