This new-old-stock-testing, physically matched pair of RCA 6L6GC output tubes was tested on our Maxi-Matcher with 400 volts on the plates and a bias of -48 volts for shorts, gas and transconductance. There were no shorts or gas and they tested as follows:
Tube One: Tube Two:
Transconductance: 2730 micromhos Transconductance: 2960 micromhos
Plate Current Draw: 70.9 Plate Current Draw: 82
(New US-made 6L6GCs typically test with plate current from the low 20s to mid 30s with transconductance from 2200 micromhos or so.) These tubes test substantially above spec for plate current draw and are not matched for plate current. If you can bias each tube separately, they will be fine and this is the reason I ran them in a single-ended amp.
These tubes have bottom, double-D getters; coarsely-crenelated round top and bottom spacers; anode radiators for cooler operation and longer life; good flashing (for this tube variety) and 043 C and mc date codes, respectively.
I am playing them in my Musical Paradise MC-3 single-ended integrated amplifier with The Eagles' seminal "Hotel California" album and they sound terrific. These tubes have great bass and sparkling highs and Glenn Frey's voice is warm and clear as a bell.
Please note that Tube Two is showing some color (Picture Seven). I let them run all day and things remained status quo.
BECAUSE OF THE BIZARRE, INTRUSIVE, CRUEL AND DRACONIAN GERMAN PACKAGING REGULATIONS -- AND THE SEVERE FINES AND PRIVACY INTRUSIONS ASSOCIATED WITH THEM -- WE NO LONGER SHIP TO GERMAN ADDRESSES. WE WILL HAPPILY SEND YOUR PACKAGE TO A NEIGHBORING COUNTRY OR MAKE SUITABLE ARRANGEMENTS.
IN 2021 WE PURCHASED 150,000 VACUUM TUBES. IF IT'S NOT LISTED, WE PROBABLY HAVE IT. PLEASE ALSO SEE OUT ETSY SISTER SITE "LOWTECHTWOO" AND/OR CALL OR TEXT US AT 202-372-6931 IF YOU DO NOT SEE WHAT YOU NEED OR HAVE ANY QUESTIONS.
1. MOST OF THE TUBES WE SELL ARE OVER 70 YEARS OLD. WE CANNOT GUARANTEE FOR FAILURES AFTER POWER UP AS THERE IS NO WAY TO DETERMINE HOW TUBES WILL INTERACT WITH YOUR ELECTRONICS OR IF THEY WERE MISTREATED IN TRANSIT; NOR IS THERE A WAY TO DETERMINE WHETHER THEY MAY HAVE FATAL FLAWS! WE CAN ONLY TEST FOR THE PARAMETERS MENTIONED ABOVE. WE CANNOT TEST FOR CATASTROPHIC FAILURE. IF A TUBE FAILS AFTER YOU GET IT, IT IS YOUR TUBE THAT HAS FAILED. THERE IS A .1 % CHANCE THIS MIGHT HAPPEN. BE WARNED. NO REFUNDS IN SUCH CASES.
2. IN OVER 8000 SALES IN BOTH ETSY STORES, WE HAVE HAD FEWER THAN A DOZEN LESS-THAN-FOUR-STAR REVIEWS OR HAVE LOST A CUSTOMER BECAUSE I REFUSED TO EITHER ISSUE A REFUND FOR A TUBE THAT WENT BAD AFTER IT HAD BEEN USED OR A BUYER KNEW NOTHING ABOUT TUBE REBRANDING AND CLAIMED THAT SOMETHING MADE BY TUNG-SOL AND BRANDED BY EMERSON WAS MADE BY EMERSON, AN ELECTRONICS COMPANY THAT NEVER MADE TUBES!
3. TUBES ARE GUARANTEED GOOD ON SHIPMENT. IF YOU FEAR DAMAGE OR LOSS OF PARCEL IN TRANSIT, PLEASE INSURE THEM! OUR SHIPPING RESPONSIBILITY ENDS WHEN THE PARCEL IS ACCEPTED AND SCANNED BY THE US POSTAL SERVICE. ETSY IS CLEAR ON THIS. SOMETIMES THERE ARE INITIAL SCANNING DELAYS. WE HAVE ACCESS TO THE SAME INFORMATION YOU DO AND IT IS YOUR RESPONSIBILITY TO DEAL WITH THE USPS SHOULD THERE BE DELAYS OR LOSS OF A SCANNED PACKAGE. PLEASE BE PATIENT FOR THE FIRST DAY OR TWO IF THE PACKAGE IS STILL MARKED AS "PRE-TRANSIT." WE SHIP THE DAY AFTER THE SALE IF THE SALE WAS AFTER 9:30 AM EASTERN TIME.
4. THIS IS NOT AMAZON. THERE WILL BE NO REPLACEMENTS FOR LOST PACKAGES OR TUBES THAT FAIL. IN PRACTICE THIS MEANS YOU TAKE ON THE RESPONSIBILITY FOR THE LOSS IF THE PACKAGE IS MARKED AS "IN TRANSIT" OR AS "DELIVERED." MAIL GETS MISPLACED, STOLEN AND LOST. SOME COUNTRIES DO NOT HAVE INTERNAL TRACKING. CHINA IS AN EXCELLENT EXAMPLE. IF YOUR COUNTRY IS SIMILAR, IT IS YOUR RESPONSIBILITY TO INTERACT WITH YOUR CUSTOMS AND POSTAL AUTHORITIES TO FIND THE PACKAGE. CUSTOMS DELAYS CAN ADD WEEKS TO DELIVERIES.
5. I BUY TUBES IN BULK. 10-15% OF THEM ARE NOT SUITABLE FOR HIGH END AUDIO APPLICATIONS. THAT LOSS RATE IS REFLECTED IN OUR PRICES. I LISTEN TO THESE TUBES IN TUBE EQUIPMENT. SOMETIMES TUBES THAT TEST WELL HAVE PROBLEMS AND SOUND AWFUL. THAT IS ALL I CAN DO. IF THERE WERE A TEST FOR FUTURE FAILURE, I WOULD USE IT. THERE ISN'T. THERE IS RISK IN LIFE. THESE PRODUCTS ARE NO LONGER MADE. THERE ARE NO MANUFACTURERS TO TAKE PRODUCT BACK BECAUSE OF DESIGN FAILURES OR QUALITY-CONTROL ISSUES. THE PRODUCT DEVELOPMENT AND IMPROVEMENT CYCLE IS OVER.