Oldies is a moving target. The format originally meant the rock and roll era of the late fifties and sixties; it now routinely covers the seventies and eighties, and a station calling itself oldies may open with Motown or with Duran Duran depending on when it last redefined itself. In this directory that ambiguity is handled by decade tags, and if you want something specific it is worth using those rather than the oldies label.
The genuinely useful thing about oldies stations is that they are one of the few formats where local and national identity survives strongly. A German oldies station plays a substantial amount of German-language material from the same decades. Dutch, Italian and Brazilian oldies stations do the same. The international rock and pop canon is there in all of them, but it sits alongside a domestic canon that never travelled, and that is the part worth hearing.
A technical note specific to this category: a lot of oldies material is transferred from analogue sources of variable quality, and some stations are streaming from compressed files that were already compressed once before. Where you hear harshness on an oldies stream it is as likely to be the source as the encoder, and a higher-bitrate station will not always fix it.
