• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

LED bias with gNFB

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Maybe my searching skills are not the best but I was unable to find a reference to this point. Is there any reason why an amplifier with LED bias on the first stage could not also use gNFB applied from the OPT secondary to the cathode of the first stage by putting a small resistor under the LED (from LED to ground) and applying the FB signal to the top of that resistor?
 
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