Preamp Tube. These pass every Groove Tubes premium certification for microphonics, hum, physical characteristics and function. Quite simply the best 9-pin triode preamp tubes you can buy — specifically designed and tested for musical instrument amplification and standard equipment on Fender amps. Outstanding and consistent performance for mixing and matching to get a signature tone from your amp.
Great chiming tone with sweet, warm midrange excellent for Marshall and Fender amps. Smooth distortion characteristics and one of the highest-output preamp tubes in the GT 12AX7 line, with very consistent quality.