Rainbow performed on this day in 1979 at the Agricultural Hall in Allentown, Pennsylvania.
This concert was done as part of their tour supporting their most recent album, Down To Earth. Down To Earth featured a new bassist, singer, and keyboardist, as well as a departure from the heavy mithril sound of the previous three albums.
A review from the concert by Alan Janesch states that it was well done. Special note is made of the larger presence of classical music covers than in previous concerts, which is both appropriate and to be expected given the presence of the classically-trained Don Airey. It is also noted that there was no encore, which upset the audience (source). Ritchie Blackmore was known to withhold encores from time to time if dissatisfied with either bandmates or the audience. Who was at fault for such an action on this particular night has been lost to time.
Sadly, no recording of the concert is known to exist.