Hum Neutralizer Circuit For Tube Amps

Have a hum in your guitar tube amp? Like everyone else? Want to get rid of it? This hum neutralizer circuit is based on a concept in the Radio Design Handbook. This circuit is a noise cancellation concept. I elevate the ground and then use the previous stage to invert the signal and then the hum is canceled out in the power tube. Very nice solution and it only costs the price of 1 resistor, a few inches of wire and installation time.
This video explains the problem, why some common fixes are not 100% effective, the oscilloscope image of the problem and then explains the remedy.
This is now a standard feature to all my vintage circuits.
Original Work, Copyright 2015 James D. Whiteside, II all rights reserved, For consideration only, no reproduction without prior permission.