old stock haltron united kingdom 6sl7gt audio tube w/ box, good used gm spec / your results will vary
old production w/ the most precious metallurgy of the tube era = more accurate sound reproduction
direct overseas import carefully curated from collections
full amplificaton test 84/85 % mutual gm (65 % good) + useful life test, and leak short gas
our unique mutual gm output test applies 225 vdc simulating actual circuits w/ filtered dc
twice tested! also supplier emissions tested ...circuit test = best test
give 100+ session hours w/ your specific amps voltage to fully settle
ships fast worldwide well packed + combined postage available
~authentic vintage hifidelity audio curation by caliacoustics~