Matrix is the safest way: UK Tube Cut Stereo PPM -1/-1 WTB -2/-2 AHDN -1/-1, -2/-2 BFS -1/-1 Help -1/-1 RS -2/-2, -3/-3 Rev -1/-1 Oldies -1G/-1G Sgt P -1/-1 MMT (EP) -1/-1/-1/-1, -2/-2/-2/-2 TB -1/-1/-1/-1, -2/-2/-2/-2 YS -1/-1, -2/-1, -3/-1 This I copied from another thread. I think it’s got most of it correct(actually all). I am sure someone will comment if there is something missing.
If the rim text starts 'The Gramophone Co Ltd' that's usually an indicator of tube but obviously there is cross over with the later 'EMI Records Ltd' (solid state) so you would have to check the matrix numbers
PPM -1/-1 WTB -2/-2 AHDN -1/-1 BFS -1/-1 Help! -1/-1 RS -2/-2 or -3/-3 although first cut -2/-2 unlikely can be found on 1970s pressings. Revolver -1/-1 SPLHCB -1/-1 White Album -1/-1/-1/-1 or -2/-2/-2/-2 or any combinations of -1 and -2 YS -1/-1 “Abbey Road” and “Let It Be” – I'm not sure if a “loud cut” exists for these albums, not in the UK anyway.
I owned AHDN and Help and thought they had “a pronounced midrange. Depending on the speakers or cartridge this might be desirable. I now have a Holland BC13 and nothing in there seems over-EQed
