San Francisco has always been a good-time town. For periods it has been a wide-open town. And no matter how tight they close the lid and no matter the 2 A.M. closing mandatory in California, it is still a pretty wide-open town.

A high-price call girl, flush from the Republican convention and an automobile dealers conclave and happily looking forward to the influx of 20,000 doctors, 8,000 furniture dealers and divers other convention delegates, put it simply. "San Francisco is the town where everyone comes to ball, baby," she said.

This spirit of abandon goes hand in hand with a liking for jazz, because jazz is, no matter how serious you get about it, romantic music by and for romantics. What could be a better place for it to flourish than a town where everybody comes to ball, baby?

Because San Francisco is a small town with the charming lines of a big city, concentrated on the tip of a peninsula in a naturally air-conditioned dreamworld it never gets TOO hot, nor TOO cold) there is a perpetual springtime air about searching for jazz. The fog is friendly; the clubs-dirty, dingy, crowded, smoky and badly run like jazz clubs everywhere-somehow seem warmer. The audiences - Nob Hill slummers, bearded bohemians, crew-cut University of California sophomores and the casual tourist, gaping at the "big name" jazz stars— are friendly. They want to tell you why they like the city, why they like its music and what Stan Getz said to them. last time they heard him and do you remember the time Duke played the Fillmore Street ballroom and Al Hibbler sang "Trees"?