Iron Butterfly was a local band. In fact, they were booked for my High School Friday Night Sports Night (the dance after the football game), but were cancelled earlier in the week. Seems that they played the Sports Night (one week earlier at a rival High School) and the police stopped the show when there was use of "bad" language!

Can't remember who filled-in, but Iron Butterfly was a local favorite, often performing at Battle of the Band concerts.

And speaking of Spirit, when we saw them as the opening act for The Moody Blues at the LA Forum, they were far better than than the Blues, but then the Blues were very "studio" and not a good "live" group.

Jim