Premium tubes professional version old production Holed Mica
Made in USA type 5963 tube marconi / Rca long plate
O getter 45° welded getter
12au7 ecc82 cv491 B329
7 pieces matched valves
Made in USA oldest production mid of 1950's golden era HiFi
Big large Dark  plate ribbed big  plate TOP quality made in U.S.A.

Great sound in Hi end amplifier pre phono input stage

super strong preamp pre amplifier driver valves for EL34 KT88 KT66 EL34 EL37 6550 350B and many more !
tubes professional can be operated under cut-off conditions for long periods without degradation

Laboratory tested with all test results on glass
Each tube has been tested strong and balanced with TV7D/U military tube tester calibrated

test results as per labels on each tube please see pictures  for details

Socket Noval B9A
Filament heater    Vf 12.6 Volt / If 0.15 Ampere / Indirect / Parallel / series ~ = AC/DC

tube valve lampe röhre tsf 진공관 真空管 HAM RADIO audio hi-end hi-fi diy POWER AMPLIFIER roehre Pre-Amplifier Preamp Pri VINTAGE stereo SE Single Ended PP Push-Pull VACUUM TUBES röhren roehre vorverstärker röhrenverstärker preamp preamplifier roehre röhre nos nib tube ovp röhren speakers field coil full range voice coil turntable

codice x box 56