The original amp, the Magnavox AMP 175, was pulled from a console stereo. My first rebuild of this amp was based on the main amp section of the Harman Kardon A300, but the design, or my execution of it, was faulty: The amp produced slewing distortion. The only solution I could find was to redesign the input and phase splitter/inverter stages and use different triode tubes. I did a complete rebuild based on the Bevois Valley design by Morgan Jones. The rebuild was successful! Slewing distortion was eliminated, and the sound is good. In this video, I talk about and demonstrate the problem, show the rebuild in stages, and reveal the results.
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