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Hum issue – solved!

Okay, it’s been so long since I’ve posted an update it’s taken me awhile to remember how I was doing it!  The strong hum issue with the amp has been fixed.  Someone much more observant than I pointed out an apparent problem with my tube socket wiring.  According to the schematic, pins 8 of V4 and V5 should be tied together.  If you look at pin 8 of V4 in the following photograph you will notice that something is missing:

Power tube wiring

Since correcting the problem the amp runs much quieter!  I’m glad the problem was discovered but I also feel kind of stupid.  I supposedly did thorough double-checks of my wiring and yet I still managed to miss something this obvious!

I’m  happy with how the amp sounds now, but I still plan to correct some lead dress issues with my AC lines feeding from the power cord socket.

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