The Hall is a former art gallery whose owner decided to convert it into a concert platform for the old masters of New Orleans jazz while they were still alive. Customers sat on hard wooden benches or stood at the back of the room. When the crowd reached 150 it was a full house.

On the night I called, Paul Barnes, 69, was playing clarinet, Chester Zardis was slapping his bass furiously at the age of 72 and trumpeter Percy Humphrey, 66, drummer Dave Oxley, 64 and banjoist Narvin Kimball, 63, seemed comparative striplings. Pianist and singer Sweet Emma Barrett was not sure when she was born.

Obviously, the personnel has changed with the passing years – trumpet player John Brunious Jr who led the band for more than two decades died this year – but the crucial point is that, after half a century, the band still exists as a symbol of New Orleans.

The PHJB spends a large amount of time on the road , and its Harrogate appearance comes at the end of a tour which has taken in Henley Festival, Chichester Cathedral, Oundle, Rotterdam, Alicante and Galway. The present line-up, aged from 31 to 88, ensures the music sticks defiantly to its venerable roots.

Tomorrow night's concert at the restored Royal Hall is part of an attractive jazz programme at Harrogate International Festival which continues next Thursday with the ebullient Clare Teal, the evergreen Buddy Greco and Ronnie Scott's Jazz Orchestra. The David Rees-Williams Trio play cabaret jazz at the Crown Hotel on Wednesday.