ecc83 mullard tube 12ax7 philips pair valves
red pip top NAT LAB laboratory science department Made in Holland Ultra rare
2 TUBES = 2 VALVES = 2 VINTAGE VACUUM TUBES = 2 röhren = two pieces
Red tipped laboratory selected15mm Long PlateDark grey plate ribbed weldedO getter haloplate with Silver tongues on rounded cornershigh quality tubes for preamplifier preamp per input phono driver stage first stage audioECC83 Double Triode Audio Frequency High GainECC83 = 12AX7 = B339 = 95-127-01 = 6L13 = CM1 = ECC83SSimilar Tubes Normally replaceable-slightly different: 0AX7 ; 12AX7A ; CV492 ; E2164Other class quality (otherwise equal): 7025 ; CV4004 ; E83CC ; M8137Other characteristic (electr. data): 12AY7 ; 6N4_ChinaOther base and other heater: 6EU7 ; ECC808Multiple differences or of other kind: 5751 ; 7729Successor Tubes 1963 ECC808 5751WABase Noval B9AFilament Heater Vf 12.6 Volts / If 0.15 Ampere / Indirect / Parallel / series AC/DCfully tested on calibrated tube tester tv7d/u
Test results as follow: 60/60 ; 50/50
code I63 DELTA △ red tip selected (reference good at 32/32 ) on tube tester calibrated TV7D/U one with geloso round logo on glass
All 2 tubes own red tip , selected nat laboratory , selected for pre amplifier stage audio
box 154
pair 2