we pride ourselves on a proprietary complimentary value-added complete refurb screen and deox process, plus free postage!
also check out our official site! new part numbers including reserve/request options and true nos sealed-box rarities
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4 old stock vintage matsu national 6ca7 el34 power preamp audio output tubes
vintage quad w/ same k code and earlier smooth top design w/ slightly larger glass envelope
the british supplied expertise and tooling via 'transfer of technology' resulted in several critical audiophile advantages:
same anodes, micas, electrode geometry, glass envelope, spot welding, grid wire spacing and cathode processing chemistry!
direct japan imports carefully curated and twice tested, plain or branded boxes included
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full conductance test 94~106~107~107 % gm (65%)+ life test pass! (life check = key feature other testers lack!)
our special gm output test applies real world 225vdc voltages w/ filtered dc, plus an impeccable gas test and leak/short check
gm scores relate to current transfer ability, whereas gain relates to signal amplification ~ a difference based on voltages
ships fast well packed worldwide ~ authentic vintage hifidelity audio curation by caliacoustics