Friday, August 5, 1966, is the day this chronicle likes best, because on it the scene's defining rivalry played out two rooms and a few blocks apart, each with its own poster. That night the Family Dog opened a weekend at the Avalon Ballroom with Big Brother and the Holding Company — Janis Joplin's band, the Avalon's own — sharing the bill with Oxford Circle, under Stanley Mouse and Alton Kelley's FD-19, the poster collectors have long called the "Dollar Bill" for its currency-parody design, with Bill Ham on lights. The very same Friday, across town at the Fillmore Auditorium, Bill Graham countered with Love — Arthur Lee's pioneering Los Angeles band — and Everpresent Fullness, on Wes Wilson's BG-21. Two houses, two poster shops, two bills, one night: the Family Dog and Bill Graham running head to head, which is the story of 1966 in miniature (both bills are documented on chickenonaunicycle's Fillmore and Family Dog lists and corroborated on Wolfgang's for catalog number, designer, and date).

The "Dollar Bill" carries a small trap worth handling honestly, and it is the kind the poster catalogs invite. FD-19 prints a four-act lineup — Big Brother, Oxford Circle, Bo Diddley, and the Sons of Adam — but those acts did not all share the Avalon stage on August 5. The night-level record shows that on Friday the 5th the Avalon had Big Brother and Oxford Circle, while Bo Diddley and the Sons of Adam played Longshoremen's Hall that same night under a separate Family Dog poster, FD-20 (also a Mouse-and-Kelley design); Bo Diddley and the Sons of Adam then moved to the Avalon on Saturday the 6th. So the poster's four names are spread across two rooms and two nights. We keep the poster's billing as the artifact records it, and note that August 5's Avalon stage specifically belonged to Big Brother and Oxford Circle. Big Brother in early August 1966 were still a local band with a national breakthrough ahead of them — a year before Monterey — and seeing them headline the Avalon on a Mouse-and-Kelley poster is the Family Dog scene at its most self-contained and confident.

Against that, Graham's Love booking is the perfect foil: an out-of-town headliner (Love were an LA band, and Arthur Lee one of rock's genuine originals) at the Fillmore, drawing the same crowd the Avalon was courting, the two promoters splitting the city on a single Friday. The Love run went August 5 and 6; the Fillmore's more famous benefit — Quicksilver, Big Brother, and the Grateful Dead among a long list — came the day after, August 7, and is a separate story.

The later years give August 5 a run of real but secondary shows, and one honest gap worth naming. In 1967, August 5 was a Saturday in the middle of the Fillmore Auditorium's Muddy Waters / Buffalo Springfield / Richie Havens run — the BG-76 booking already anchored on its August 1 opening. In 1968, August 5 was a Monday one-night special at the Fillmore West that is a small landmark of its own: Ornette Coleman, the architect of free jazz, playing a Bill Graham room. The piece survives in the catalogs as AOR-2.80, filed among the "unusual Fillmore shows," its lettering laid over a page of Coleman's own score; the designer is given as "Dore" on the catalog listing we could reach, but the attribution is thin enough that we flag it for confirmation rather than state it flatly. In 1969, August 5 opened a Fillmore West run — Paul Butterfield with It's a Beautiful Day and SRC — on David Singer's BG-185, a poster with its own footnote: it advertised Fleetwood Mac, who did not play, It's a Beautiful Day stepping in, which makes BG-185 one of the scene's "wrong lineup" posters, a printed record of a show that did not quite happen as designed. Only 1965 is a true blank: the scene did not exist yet.

Five Augusts, then, but August 5 belongs to 1966 — Big Brother at the Avalon and Love at the Fillmore, Mouse-and-Kelley against Wes Wilson, the Family Dog against Bill Graham, the whole competitive engine of the ballroom scene running on a single Friday night.