RCA 5963 "TRUE NOS" PREMIUM INDUSTRIAL GRADE 12AU7 Platinum Matched on AT1000

RCA 5963 (12AU7) Tubes (TRUE NOS) Premium Industrial Grade 12AU7 – TESTS NOS Long 17mm Grey Plates – Single “Halo” Getter Matching Production Date Codes: “61-39” 1961-Week 39 These 5963 tubes were made by RCA for Burroughs and are very heavy duty high quality 12AU7’s designed to withstand multiple off/on cycles and run 24 hours a day… They are made to very high standards and always test very consistent… They are definitely a step up from the standard 12AU7 and will put any Chinese or Russian equivalent to shame… Triple Platinum Matched on Amplitrex AT1000 Amplitrex AT1000 Test Results 95%+ GM = Within NOS Specs 90%+ EM = Within NOS Specs (GM) Mutual Conductance 2200 = SPEC (EM) Emission 8.5 gV = SPEC Noise Test (Mu) Tube Gain TUBE #1 2230/2200 (101.4/100.0%) 8.5/8.3 (100.0 /97.6%) 5/5 17.0 17.0 TUBE #2 2250 /2200 (102.3/100.0%) 8.4 /8.2 (98.8/96.5%) 5/5 16.8 17.0 TUBE #3 N/A N/A N/A TUBE #4 N/A N/A N/A PERFECT = 0.0% (5% or less = Outstanding) Balance (Balance Goal = Mhos > 5% / Gv > 10%) Tube 1: A to B = Mhos – 1.4% Gv – 2.4% Tube 2: A to B = Mhos – 2.3% Gv – 2.4% Match (Tube 1 to Tube 2) (Match Goal = Mhos > 5% / Gv > 10%) Tube 1A to 2A = Mhos – 0.9% Gv – 1.2% Tube 1B to 2B = Mhos – 0.0% Gv – 1.2% Noise Test Scale: 5 = Ultra Low; 4 = Very Very Low; 3 Very Low Tube Gain Scale : 17 Mu (+ or -) 3 Mu = Within Factory Specs BULLz TUBEz About BULLzTUBEz: I’ve been an Audiophile for over 50 years, 2 time National Champion in Car Audio and owned a chain of Car Stereo Stores… I have a massive collection of vacuum tubes specializing in mostly esoteric tubes but we have just about any tube you need. Just check the store for the listed inventory. If you have a request just send a message to NOVA.76 through the eBay messaging system… About our TUBEz: All tubes are tested with the Audiophile in mind for SHORTS, GAS, MUTUAL CONDUCTANCE and NOISE (large tube lots are not tested for noise). All my tubes are tested thoroughly on an Amplitrex AT1000… My backup tube testers are an AVO MKiv and another Amplitrex AT1000… I WILL NOT GUARANTEE THAT OUR READINGS WILL MATCH YOUR READINGS… I stand behind everything we sell… My goal is to “Create a Positive Experience” for my customers… Warranties: Used or vintage items are sold as is with no warranty beyond the description and photographs provided on the listing. Returns will NOT be accepted for reasons such as: ordered the wrong item, changed mind, not what I thought it was, wrong color ordered, wrong item ordered or tube readings don’t match my tester. Any exceptions are on a case by case basis… Shipping: Domestic Shipping to the continental United States will be by the US Postal Service (USPS) including free tracking. Some items listed will ship free and will be clearly listed as “free Shipping”. Items not listed as free shipping will be for the cost of packaging plus shipping only, no extra charge will be added to the USPS fee. INTERNATIONAL BUYERS PLEASE CHECK THE SHIPPING CHARGES PRIOR TO BIDDING International Shipping will be offered for select items and will be clearly identified in the listings Shipping & Payment tab. Shipping will be by the ” eBay International Standard Shipping ” and be made available as a shipping option at check-out. Shipping costs to international locations will be paid by the buyer. The shipping and handling cost will be clearly identified at check-out. THERE ARE NO RETURNS ON INTERNATIONAL SHIPPING , apart from the exceptions as dictated by eBay… Please note the following: Import duties, taxes and charges are not included in the item price or shipping charges. These charges are solely the buyer’s responsibility. Please check with your country’s customs office to determine what these additional costs will be prior to bidding/buying. These charges are normally collected by the delivering freight (shipping) company or when you pick the item up – do not confuse them for additional shipping charges. We do not mark merchandise values below value or mark items as ‘gifts’ – US and International government regulations prohibit such behavior.