an audiophile classic, very rare pq heerlen e88cc gold pins w/ musical mid euphony vivid detail and lush sibilance
twice tested! digitally matched and analog verified, audio grade matched 1962 pair, very hard to find collectibles
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the special amperex star series are the top echelon w/ unparalleled vocal fidelity and transparent linear response
these early holland tubes are legendary for their warmth, cymbal-style resolve and linear frequency response
full body and tone articulation, low/high register intimate holographics via strategically less rf than amperex usa
legendary philips 2nd/3rd stage harmonics illuminate and color stereos preamps tube mics+ more
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these limited run types have more precious tube-era metals and warmth = reproduces sound more accurately
premium quality series w/ improved cathode durability for mission critical instrument grade apps
e88cc also benefit from more mid bloom compared to 6dj8 or 7308, a wider frequency tune! 6922 equivalent
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full amplificaton balanced test 101/97~99/98 % gm (65 % good) + useful life test didnt move the meter!
our dynamic output gm test applies 225 vdc simulating actual operations w/ filtered dc + leak short gas check
simply put the higher mutual gm scores = amplification capability and gain / bass response
also supplier double checked via amplitrex for pure digital accuracy 10.3/10.8 ~ 10.3/10.4 ma pristine match
while your bench results will always vary ...the circuit test = best test
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all tubes also undergo a special value-added proprietary refurb process, one of a kind seller qc!
plus full sound auditioned w/ closed back ultra high resolution monitors and aira preamps
give several sessions or up to 100+ hours w/ your specific amps voltage (break-in is important)
ships well packed worldwide + combined postage available 
(1 more limited run pair available via buy it now)
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~authentic vintage hifidelity audio curation by caliacoustics~