Just took a listen to refresh my memory. Definitely a very growly tone. Absolutely sounds like some fresh Rotosounds and a P. Even if it was the Jazz, maybe Jonesy was just playing around with some settings on his amp for that show? The second disc is very uncharacteristic of JPJ's "regular" tone. IMO he had a very growly, almost trebly tone for the second disc of that album... just did some googling... Heartbreaker is on disc 2, all of which was recorded April 1 1971 at the Paris Theatre in London.
Great album, my only complaint about this album is that I prefer when JPJ would play bass (ex: RAH 1970) on Somethin' Else and not piano.
"TK-421 why aren't you at your post?"