Groove Tubes GT-12AY7 S Select, Single Overview
Groove Tubes puts its GT-12AY7 lamps through rigorous testing for microphonics, hum, physical and operational characteristics. These are simply the best 9 pin triode tubes you can find for your preamp. They are designed and tested specifically for amplifying musical instruments and are standard on Fender amps.
The Groove Tubes GT-12AY7 Select Preamp Tube is closest in specification to a 12AX7 and can be exchanged with a slight drop in gain. Most companies changed over to the 12AX7 as it became more common. This valve can be tried in later Marshall amplifiers in the first gain position to drop the background noise and lower the gain level to plexi or early 70’s vintage gain levels with its returned wider frequency response.
