Question about live amplification | Fab forum

Wondering about their sound set-up when performing live. I've always been under the impression that they were put through venue PAs, most of which were not up to the job and affected their feelings on live performance. Especially when they got to baseball stadiums. Got caught up in a discussion on YouTube about whether they just went through their own amps or whether also plugged into venue PAs, and now I'm questioning my memories of the complaints about what venues were set up to handle, and how they weren't set up to handle The Beatles. Anyone able to help?