Re: weird overdubs
My favourite is to listen for bleed-through on remastered recordings. My copy of 'A Love Supreme' (kindly donated by a member of this forum a couple of years ago) has obvious bleed-through on 'Resolution' and a few other parts. It's like pre-delay but exaggerated. A lot of that has to do with incorrect storage of tapes and the remasters being done a decade or two later. It still shocks me the way that some of the most important master tapes of the last three generations have been stored so poorly.