The GT-12AX7 / ECC83-S lamps have passed all of Groove Tubes' rigorous tests for microphonics, hum, physical characteristics and operation. These are simply the best 9 pin triode lights you can find. They are designed and tested specifically for amplifying musical instruments and are standard on Fender amps. They offer exceptional performance and sustained yield. You won't find a better way to create your signature sound with your amp. Our preamp tube delivering the highest level of gain. Its incredible power makes it an ideal choice for powering modern and complex high gain circuits. It produces a dense, powerful and relatively bright sound, and can really revive a tired or weak old amp, or even boost a new amp equipped with standard tubes.
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