I can't keep away from jazz personally, but only really that golden period from the mid 60-s to the mid 70's. There's a lot of good stuff from before and later, but that period offers so many more chances of finding those nuggets! However, I do like to investigate a lot of cheesy lounge music, and my favourite source (though not strictly a genre) is library music from that same era. There's so much amazing stuff throughout this area of music, it's just ridiculous, but it's not cheap (unless you get lucky at carboot sales/goodwills) which I often have

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