Sent in by Roy:
In the late fifties and early sixties, The Black Lion pub on the corner of Blackfriars Street and Chapel Street was also a jazz club. Jazz nights were on Sunday evenings on the first floor.
Access was by membership card.
The resident band's name was possibly Blue Notes jazz band.
Often the same ardent jazz enthusiasts who frequented The Thatched House on the Saturday night would assemble on the Sunday evening in the Black Lion.