Do I take it that last year's rear speakers / screen behind the sound tower was just for the 50th Anniversary? On Saturday I was 20 yards in front of the top Mario's Ice Cream Van, just off to the bar side, and the sound quality & volume was pretty poor. It was hard to hear the on stage banter and difficult to make out a lot of the lyrics. The problem seemed to be the sound 'blowing away' with the wind, a problem largely alleviated by last year's rear speakers.
Now you come to mention it yes the speakers there last year were not in place this year so hopefully the organisers will put them in place again next year.