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.
Tubes do not have to close matched guessing you think 1% match. Performed a test using PPP with very close matched and poorly matched tubes. Did not hear a difference. Same brand is more important.
