7581A GE GENERAL ELECTRIC VINTAGE TUBE 7581 6L6GC NOS SLEEVE OF 5 eTRACER

SLEEVE OF 5 GENERAL ELECTRIC 7581A \ KT66 VINTAGE VACUUM TUBES. These are 35W direct replacements for 6L6GC tubes, and the most rare variant in existence. Sleeves like this only come by once in a lifetime, it's difficult to even find a matched pair of these!

Includes one identical matched quad, and one bonus GE manufactured Westinghouse (SAME CONSTRUCTION TUBE). Tubes tested on both our eTracer, Maximatcher, and Hickok 800A, with results for mA, Rp, Gm, and Mu.

Corners test simulates real world variations in plate current when voltage spikes naturally occur in the circuit. First four tubes test well above nominal, plate current is matched within 10%. The fifth tube is Westinghouse labeled, but made by GE and the same construction.

This last tube tests lower but is still very viable. Tubes have also been audio tested in a 1963 blonde \ blackface Fender Tremolux, and sound great. Remember to bias your amp (If needed) with a qualified technician when changing your power tubes. ETracer: Tube #1 - mA = 48.1 Rp = 1660 Gm = 4586 Mu = 7.6 Corners = Pass Tube #2 - mA = 49.2 Rp = 1638 Gm = 4628 Mu = 7.6 Corners = Pass.

Tube #3 - mA = 45.2 Rp = 1716 Gm = 4566 Mu = 7.8 Corners = Pass. Tube #4 - mA = 47.8 Rp = 1640 Gm = 4680 Mu = 7.7 Corners = Pass Tube #5 - mA = 34.8 Rp = 2094 Gm = 3907 Mu = 8.2 Corners = Pass ________________________________________________ Maximatcher \ Hickok 800A. Tube #1 - Gm = 6000 / Plate Current = 48.0.

Tube #2 - Gm = 4600 / Plate Current = 49.4. Tube #3 - Gm = 4600 / Plate Current = 45.1.

Tube #4 - Gm = 4600 / Plate Current = 47.8. Tube #5 - Gm = 3900 / Plate Current = 35.1. Nominal \ New = 4100 \ Minimum Good = 2000. Past 30 days, we cannot offer any guarantees a vintage item will continue to function. Please keep any boxes, pins or labeling intact.

Test Results: First, we test all of our tubes, in both a calibrated tube tester, and perform a live audio test in guitar, hifi and vocal amplifiers. Our testing practices are stringent, and have given us well over a decade of satisfied clients. Still we cannot guarantee exact test result numbers or data, nor can we foresee the results you will have using our parts in your equipment.

This is a widely criticized word that many electronics experts and hobbyists \ enthusiasts do not like to hear unless the item is brand new, sealed in the box. Many tube buyers only know vintage tubes by the term "NOS" and will not type "vintage" when searching for what they are looking for. Therefore, when we list "NOS" in the title, we are only describing a vintage tube. When a tube is new in box, we will combine that with the term "NIB", or "New In Box".

We will also list that the item is "NIB", "NOS", or "new in box", when a vintage item meets a certain threshold of visual quality combined with test data for it's age and type. This is normal for items stored for many decades in sometimes less than ideal climates. These items also have been understandably handled and changed hands many times over their life. This usually results in less than perfect cosmetic condition, but by no means indicates the item is used.

Most audio experts are in 100% agreement on this. We hope this clears up the title term NOS for some buyers who have or will inquire about this. We are not trying to misrepresent our items, we are simply attempting to put our listings into the hands of those who want to see them. Performance Of Vintage Items: We cannot guarantee a vintage item will perform the same with or in your equipment as it did in ours, or that a vintage item will continue to function once it is used. The item "7581A GE GENERAL ELECTRIC VINTAGE TUBE 7581 6L6GC NOS SLEEVE OF 5 eTRACER" is in sale since Saturday, June 2, 2018.

This item is in the category "Consumer Electronics\Vintage Electronics\Vintage Audio & Video\Vintage Parts & Accessories\Vintage Tubes & Tube Sockets". The seller is "lakeland_music" and is located in Lakeland, Florida. This item can be shipped worldwide.

Model: 7581A
Country/Region of Manufacture: United States
Bundle Listing: No
Type: NOS Tube
MPN: Does Not Apply
Brand: GE