Yet another surprise in the now-annual parade of previously unreleased gems from the big names of the past, this is especially interesting. As originally revealed by Monk biographer Robin DG Kelley, the teenage promoter of this Sunday-afternoon concert succeeded in bringing together a mixed-race audience during the tense times typified by the Democrat Convention the previous August.

Perhaps for that reason, what we have is a particularly energetic performance lasting 47 minutes (including tuning-up and applause), that is typified by Monk's lengthy and energetic solo exploration of ‘Don't Blame Me’. And, while I wasn't necessarily looking forward to another exposure to Charlie Rouse (especially comparatively late in his Monk career), he plays with considerable invention and enthusiasm, perhaps because the rhythm section (also late on in their affiliation) are on top form, typified by a long bowed solo from Gales on ‘Well You Needn't’ which actually holds the interest, as does his pizzicato solo on ‘Blue Monk’ that includes a chorus played beyond the bridge of his instrument.

Riley is also good on the same long number, and introduces an unexpected double-time feel throughout the lively ‘Ruby My Dear’.

Despite the release over the years of one too many live Monk quartet recordings, this one turns out to be a pleasant surprise and, as they used to say, it's good enough to keep.