It's really amazing how good The Beatles sounded live with such limited primitive crappy sound systems of the time,but they were so great that they would have even sounded good playing out of of cave.
There is an online interview with Roger Daltry,Roger's Journey With The Who in The Sun http://www.thesun.co.uk/sol/homepage/showbiz/sftw/607170/Rogers-journey-with-The-Who.html
and he was asked if The Who had screaming girls at a certain point,and he said after Can't Explain they did. He said it was the screaming teenage era and every band had them on their way up. He said it was fun at first but the trouble for a performer when you are that young and inexperienced is that you start to judge your performances on the amount they scream,he said it's nonsense which is why Lennon gave up. He also said that The Who's manager turned their image overnight from scruffy rockers to Mods.
When The Beatles played live in 1963,64,65 & 66 they only had 100 watt amplifiers,no feedback monitors so they couldn't hear themselves sing and play,plus the screaming crowds and that's why they gave up touring.
George Harrison says in The Beatles Anthology video series,that for their August 1965 Shea Stadium concerts, special 100 watt amplifiers were made and that they went up from only 30 watts before. Given how limited and primitive the sound systems were then,it's amazing they sounded as good as they did live.But it was impossible for *anyone* to sound great on those kind of limited,primitive sound systems of the time.
Former Kiss guitarist Bob Kulick who produced the heavy metal Beatles tribute album, Butchering The Beatles, said he saw The Beatles in concert in 1966 and he said he could hear parts of Baby's In Black & Paperback Writer and they sounded amazing.
A guy Steve from Canada said on Artist Facts,that he saw The Beatles live in 1966 and The Stones in 1996(and the sound systems by then were a zillion times better!) and he said don't get me wrong,The Stones were great but they were no match for The Beatles and he called The Beatles The Greatest Band Of All Time.
The Beatles started out playing 8 hours a night in the sleazy strip clubs of Hamburg Germany,taking speed pills to stay awake,wearing tight black leather jackets and pants,smoking and cursing on stage,and had sex with so many young women groupies including the strippers in those clubs,they were successful there. They also played successfully live in The Cavern Club for several years in the early 1960's.
John and George especially hated Beatle Mania,and George says in The Anthology series, that it took a toll on their nervous systems, they had no life either trapped in hotel rooms most of the time. They wanted to be popular & successful as every band does, but they didn't want or ask for the hysteria. John says in his 1975 Tomorrow Show interview that the screaming wasn't doing the music any good,and that things would break down and nobody would know.
The Beatles sound great on their live roof top January 1969 concert in The Let It Be Film, and the sound systems had improved by then,(although still very limited compared to today's) and there were no more screaming crowds.
Paul was playing guitar and writing songs at 14 and he started soon after his beloved nurse and midwife mother Mary died of breast cancer, and he wrote the beautiful song Let It Be after he had a real seeming dream where he saw her alive again and she told him to just accept things as they are. He says in his authorized biography, that when he woke up he thought how great it was to see her alive again.
And there is this very good article by Collin Fleming from The Atlantic, 50 Years Later: The Greatest Beatles Performance Of All Time http://www.theatlantic.com/entertainment/archive/2013/10/50-years-later-the-greatest-beatles-performance-of-all-time/280801/
And there used to be the full video of The Beatles February 1964 Washington Colosseum and there were over 1,000 likes and many people were saying what Frank and Jack say to this now only audio version of this concert,( many people on youtube are saying why are many of The Beatles videos gone off of youtube now and some are saying it's because of UMG_MK and I don't know what this is.) that it's amazing that with such crappy sound systems of those days and no feedback monitors so they couldn't even hear themselves singing and playing and many said they still sound so good and great and some say this Washington concert proves what a great live band they were and before they got so tired of all of the Beatlemania garbage they had to put up with all of the screaming drowning out their great music.