No 45 rpms or d-to-d, but here are a sampling of some baroque/early music LPs to pursue that are exceptionally well recorded with much more stylish/interesting performances. They will all challenge the reproduction abilities of your system.
Bach: Brandenburg Concertos 4 & 5, Timegate TG 234 (by reputation, I've never found a copy to hear for myself, recrded by Peter McGrath as a demo LP for DCM Time Window speakers.)
Vivaldi & Samartini, Concertos, Warchal/SlovakChmOrc, Klimo OW 006 (oop, from an outstanding series of Baroque recordings produced by the German audio firm Klimo)
Music for Baroque Cornett and viola da gamba, Klimo OW 004 (not an ensemble, just the two instruments)
Musique Arabo-Andalouse, Paniagua/AtrmMMadrid, Harmonia Mundi HM 389
Musique de la Grece Antique, Paniagua/AtrmMMadrid, Harmonia Mundi HM 1015
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