The BBC online archives are possibly more accessible and interesting than those at the British Library.
The BBC was nearly ten years old when it installed its first recording machine, but tapes and discs soon began to pile up in Broadcasting House.
Through broadcasts, internal BBC interviews and recordings never before released in full, some of the BBC’s archive pioneers explain how – and why – they set about collecting, selecting and organising voices and sounds in the 1930s and 40s. The department was variously named over the years, as its role in preserving the BBC’s output grew and evolved, but today it is best known as the BBC Sound Archive.
One of my favourite recordings is Cassius Clay Meeting the Beatles http://www.bbc.co.uk/programmes/b00r8b1k You can also download mp3 recordings of this and other Radio 4 Music Archive recordings if you would like to do this