CV492 ECC83 12AX7 Brimar KB/FD grey Plate Used Old Stock Valve Tube Code 4A0/1573 1960 1573 = designation code for brimar cv492/CV4004 Hickok gm 1700/1900 mhos gm
eBay
Tested for shorts and leaks. Good filament. Bottom pins have slight greenish corrosion as seen in photo.
eBay
What you see is what you get. Sold as is.
eBay
The plate current is a bit low, but the transconductance very high. GM (mA/V) - 1.6. ia (mA) - 1.2. Data Book Specification. GM (mA/V) - 1.8. ia (mA) - 0.8.
eBay
CV4004 M8137 ECC83 12AX7 Valve Tube. Mullard, British Made. Used, Supplied in White Box. Box Plates, Halo Getter.
eBay
2x MAZDA ECC83 Valves. NOS specification: Ia = 1.2(mA), gm = 1.6(mA/V). This valve has also been tested in amplifier without any noise. Ia1 = 1.45(mA), gm1 = 1.8(mA/V). Ia2 = 1.55(mA), gm2 = 1.75(mA/V).
eBay
26.2 / 31.1 B7B. And for good reason, it is objectively one of the most musical tubes ever produced, and can reproduce the human voice, especially female voices, with shocking realism. It’s been said that the Mullard sound can be most likened to a warm British jacket of the finest tweed.
eBay
Matched Quad (4 tubes). Quad is matched within 10% for both gain and conductance. We stand behind our products. Signal Format: Analog. Date First Available: September 11, 2015. Is Discontinued By Manufacturer: No.
eBay