For what I can remember (I was a little child the only time I've seen them live) I don't think there were big differences between live volumes in that era...
...In the 1970s you can compare Queen volume to Led Zeppelin one, I think while in the 1980s the live sound became less rough than in the past and so a higher quality (not volume) was needed...
When I saw them in Milan, I don't remember I was shocked by an excessive volume...
Ciao
Albyboy
I remember reading some where, that Queen had the loudest of any volume settings in concerts(mind you for mainstream acts), you can pretty much tell in some bootlegs if you compare them with other bands
All through the 70's, it was often said that the 3 loudest bands were Zeppelin, The Who, and Queen, in that order, I believe. And there were all kinds of people who wanted it stopped in the name of hearing loss!
In fact, I'd give my eye teeth to find this article again, but I remember that once, as a teen into Queen in the late 70's, my dad clipped out this newspaper/magazine article that said that some rock music caused impotence and mental sluggishness, and Queen were among the most guilty! It was hilarious - it named like some 30 or 40 bands, at least. Something about the rhythms, if I remember. What a bunch o' crap! I chalked that "study" up to the Anita-Bryant-loving-homophobes of the decade who would grasp at any straw to slander homosexuals (of which Freddie was strongly suspected, but not yet definitely known). I made sure I told my dad where he could put the article for safe keeping...
According the the Guinness Book of World Records, the band of the 80's, Manowar, is currently the loudest. As for the 70's, I can't say anything that hasn't been said, except I know Deep Purple were accredited to their loudness.
When Queen played 2002 with Phil Collins, he said something like Queen being the loudest band ever. I also recall that after that partivular gig, he wanted to cease playing live because of ear damages... So, those two old ladies (i.e. Roger and Brian) are still rocking away...