Thursday, September 8, 1966: the Blues Project, second-to-last night of their Matrix week.

Six consecutive nights in a hundred-capacity room is a residency, not a booking, and it is the shape the Matrix used almost exclusively. The ballrooms ran Friday-and-Saturday weekends for a thousand people with a commissioned poster; Marty Balin's club ran one act for the better part of a week for a few dozen, and printed nothing. The two models were four blocks apart and covered between them most of what live music in San Francisco actually was.

That difference is why this chronicle, organised around posters, has a systematic hole exactly where the Matrix sits. A week like this one leaves a line per night in a venue list and no artifact at all. The Fillmore's equivalent week left a Wes Wilson sheet that now sells for hundreds of dollars.

The band finishing the week would record *Projections* within weeks and be gone inside two years.