9 pin miniature preamp tube (Amplification Factor =100). This ubiquitous Chinese tube is straightforward and bright. Its high gain gives it some bite, too. In overdrive, it brings out the highs and offers easy access to harmonic sustain. For more information about our 12AX7 tubes, see our tech corner article on 12AX7s.

9 pin miniature preamp tube (Amplification Factor = 17)

7025 - 9 pin miniature preamp tube Made in China Lower hum/noise version of a 12AX7/ECC83