None of the Stadiums, but especuially the Rockpile, had much of a "sound system" in the 60's. The speakers were often out of sync, so you would get an annoying echo effect from the announcers. A Band was commonplace in the 60's, at least in the AFL.
They didn't march or move like the Colts or Redskins. They had a small platform in the corner, and that was it. We had a band and I remember bands at; Kansas City, the Jets, Denver and possibly Oakland.