British Library Sound Archive

The British Library Sound Archive (formerly the British Institute of Recorded Sound; also known as the National Sound Archive (NSA)) in London, England is among the largest collections of recorded sound in the world, including music, spoken word and ambient recordings.

It holds more than six million recordings, including over a million discs and 200,000 tapes. These include commercial record releases, chiefly from the UK, but with some from overseas, radio broadcasts (many from the BBC Sound Archive) and privately made recordings.

More information on the Wikipedia page