Just found this website, and I'm frankly stunned that I've never come across it before.
this is a treasure trove of swing and jazz music, in the form of the "Jazz Rhythm" radio show archives - there's so much incredible music, not to mention information on the music, bands, artists and jazz history on here I hardly know where to start describing it. Many rare recordings, and the audio quality is generally superb. Well worth spending some time on - I've spent a large chunk of today listening to a some of the content, and it's been blissful...
http://www.jazzhotbigstep.com/
Rhythm Jazz Archives
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