Penta / Shuguang 12AX7A Triode. Single
This high impedance amplifier triode was designed specifically for audio use and has a high amplification factor of 100.
This valve is still found in todays designs of hi-fi audio amplifiers. In the classic Mullard designs of the 1950's and 1960's the valve's two halves were used as second stage amplification and cathode coupled phase splitter.
The phase splitter being required so that the push-pull output stage was driven correctly.
The envelope is 21 mm in diameter and the average diameter for B9A valves is 20 mm. Length excluding pins is 48 mm.
The Penta / Shuguang 12AX7A is made in China by the Shuguang factory exclusively for Penta Laboratories.
Equivalent to: ECC83 - B339 - CV492