Once again, it depends on the definition of “Rock” music. If it means charted on the rock and roll portion of Billboard’s Top 100 then some orchestras did in fact qualify, as would vocal ensembles like The Ray Conniff Singers.
If it means carting with more than one song, I would point to the New Christy Minstrals in the mid to late 1960s. They had over 20 members and regulary had songs on the rock and roll charts (at least two that I can recall were in the top 20).
On the 1972 tour of Europe the Grateful Dead only had 7
Jerry Garcia - guitar, vocals
Bob Weir - guitar, vocals
Phil Lesh - bass, vocals
Pigpen - organ, harmonica, vocals
Keith Godchaux - piano, vocals
Donna Jean Godchaux - vocals
Bill Kreutzman - drums
I don’t think they every got more dense than that - six was the usual working number.
The late 60’s / 70’s horn-supplemented rock bands ala “Chicago” might be a place to look. There was one called “Ten Wheel Drive” which had 10 members, of course (apparently lacking the sense of irony which would later cause the “Ben Folds Five” to be applied to a trio). A lot of the examples listed are supplemental musicians. It’s hard to say what an “official” band member is.
Trivia question - what was the name of Ten Wheel Drive’s female vocalist? And, yes, I know without looking it up for some reason.
Actually, I would say the Dead’s usual working number was 5 - on albums they credited lyricist Robert Hunter as a member of the band, but he didn’t perform. Actually, that brings up a question - are we going to count non-performing songwriters credited as band members? Not that many cases of it, I admit.
Genya Ravan (sp?)
Tower of Power had 14 members at one point.
Blood, Sweat & Tears had 9 members, I think, on their breakthrough album.
Band-Aid or the “We are the World” rip-off of Band-Aid had plenty of members, plus they both hit the Billboard rock charts. So I submit the larger of those, probably the “We are the world” band.
Was Chicago XXVI referring to something other than band members?
I guess I should pipe in with the ELO lineup. The group never had more than seven members at any given time. The last time that happened was on the Out of the Blue album:
Jeff Lynne, Richard Tandy, Kelly Grocutt, Bev Bevan, Mik Kaminski, Hugh McDowell, and Melvyn Gale.
With Discovery the string section (Mik, Melvyn, and Hugh) went on to form Violinski. The group remained a quartet until Balance of Power which did not inclue Grocutt (who had since left to have a solo career.
The new ELO consists of Lynne and Tandy from the old days (both of whom were in The Move prior to it’s transformation into ELO), Rosie Vela (Jeff’s girlfriend), Greg and Matt Bissonette (who played with David Lee Roth on his solo tour, how’s THAT for a change of style!), Marc Mann, and Peggy Baldwin and Nancy Stein-Ross on cellos.
I finally got to see the PBS special (which is coming out on DVD in November - I have pre-ordered) and they sound great! Check it out if you get a chance.