"super strong quad set in boxes...all (4) 100% or higher (this is better than new, as reference min = 70%) -- Matched with Amplitrex AT-1000 (see test reports below) MATCHED, beautiful sounding & testing late 1960's, early production black plate (the 6 hole, horseshoe, 38mm black plate ). early - mid 1960s dates, quiet performance, and with original RCA boxes! See detailed test reports below."
MATCHED QUAD of 1960s RCA 6L6GC. These early tubes have the 6 hole black plate, single side getters, and horseshoe finished top.
They're used and working perfectly ... strong performers and they're current matched (balanced), ready to go in your amp. All (4) have original RCA boxes. Each tube displayed excellent projected life, as confirmed using the established filament drop life test. These tubes will serve you well and they sound great!
RCA introduced the now famous black plate 6L6GC sometime during the very late 1950s. Backwards compatible in all 6L6 circuits, the GC was intended to replace and outperform, producing high power, and under punishingly high plate voltage situations. The 6L6GC was related to, and designed to compete with some of the last super HiFi power tubes of the era, including the also excellent 5881. RCA's version of black plate 6L6GC's are arguably the best "GC" that America produced. They are detailed, powerful and much smoother than modern tubes. Long life and terrific tone.
They were precision plate current matched QUAD, so all (4) plates have close current (iP) (tests performed on Lab calibrated tester @ plate 250V) and incredibly close transconducance/Mu (mhos, GAIN). They will serve your purpose well whether it's for vintage HiFi Fisher, Pilot, EICO, McIntosh, Marantz, Audio Research, Altec Lansing -- or for your vintage Fender, Mesa or Marshall guitar amp. The 1950s & 60s 6L6GC Black Plate is completely backwards compatible with any circuit that calls for 6L6 (KT66 too). These were the pinnacle of RCA's quality & design and will never be made again. This ruggedized, powerful tube has the detailed sound and long life few other power tubes can match.
This is the 6L6 that all others are judged by! They have a predictibly excellent sound and LONG life span. If you are currently using modern tubes, listening results will be amazing and immediate.
Long cherished by Fender amp players. Your Black & Silver faced amps likely left the showroom with genuine RCA tubes like these (back in the 1960s).
All were triple checked, no shorts and QUIET & CLEAN to EAR when tested in amplifier. They have some hours of burn in and use, which is excellent for immediate enjoyment. (other claimed "new" or 0 hours tubes require a long time to break-in to be relaible with good sound -- instead you're smarter to choose these; they have surpassed that break-in point, and provide fuller, immediate enjoyment, and more stabilized characteristics in the near and long term for your amp).
Actual tubes for sale are shown below, exhibit A, C, D, E. They were put away as spares about 40 years ago. Cosmetics are very nice. Please view Exhibit A,B,C,D for full description and test reports. This QUAD was throughly tested in multiple testers and played with music. Quiet, matched quad set, all early 1960s, close dates, identical construction ... spanning from Oct, 1963 to Oct, 1969.
Guaranteed working great on arrival ( no DOA ).
This really is the most throughly tested, fussed over & closest matching set you could ever find ... and they always sell quickly.
They were precision plate current matched QUAD, so all (4) plates have close current (iP) (tests performed on Lab calibrated tester @ plate 250V) and incredibly close transconducance/Mu (mhos, GAIN). They will serve your purpose well! Perfect for vintage HiFi Fisher, Pilot, EICO, Altec Lansing -- or for your vintage Fender, Mesa or Marshall guitar amp. The 1950s & 60s 6L6GC Black Plate is completely backwards compatible with any circuit that calls for 6L6 (KT66 too). These were the pinnacle of RCA's quality & design and will never be made again. This ruggedized tube has the detailed sound and long life few other power tubes can match.
All were triple checked, no shorts and QUIET & CLEAN to EAR when tested in amplifier.
Exhibit B -- for easy reference shows real live test, Dynamic Emissions at FULL LOAD, All (4) tubes perform 105% (or better).
Dealers far and wide can no longer find these early units, as they haven't been made for nearly 40 years ++. This QUAD: plates are incrediblely close in Current (iP & transconductance .... they are all very close production .. dating from the late 1960's (see exhibits C,D, & E).
Cosmetics are also near mint. Strong and quiet, no gas or shorts, no microphonics at all. They were carefully checked and played with music -- for full details please read the reports in exhibit C,D,E below, for date codes and test results. As stored for many years, in the very old original boxes -- so they have a little wear, stains & foxing).
Again, these are they are the early version of the RCA 6l6GC ... 6 hole black plate ,single side getter, horshoe top -- the real McCoy! Study the actual tubes in exhibits A,B,C,D & E.
If you're currently a user of modern tubes then these will make a world of difference in your sound — a real upgrade and a treat for your ears -- cleaner & clearer. Far more overall detail you can really hear .
This QUAD is the best you'll see on here & most throughly checked and CLOSELY matching ... so I really need to repeat, they always sell very quickly. And with nearly perfectly matched ip & mhos -- you just don't see that very often.
Buy Now to avoid a bidder’s war.
Check my 100% feedback... All customers are delighted with these very old, wonderful sounding tubes.
Overseas buyers OK. Experienced fast shipping, safest crush-proof double box packing w/tracking # via email.
100% happy customers on all tubes and old audio items.
