This is just an FYI for anyone running a home off solar and experiences mechanical hum from Toroids
I have a couple of EL34 monoblocks with large-ish Toroids, I noticed after I went solar, and a far bit of household rewiring, that the Toroids had an intermittent pulsing mechanical hum. Voltage is completely on spec from the inverter., so no over voltage. I traced it to my glorious coffee machine, not a hard job because the comforting sound of the coffee machine pulsing in the morning is etched into my brain. Coffee machine can't go anywhere without a fight, so I decided to try DC blockers as per Rod Elliots spec.
Hum is gone and my coffee has brighter highs with a clearer image, I can literally taste where in the field it was picked. Seriously though, DC blockers on amp, not on coffee machine.
I have a couple of EL34 monoblocks with large-ish Toroids, I noticed after I went solar, and a far bit of household rewiring, that the Toroids had an intermittent pulsing mechanical hum. Voltage is completely on spec from the inverter., so no over voltage. I traced it to my glorious coffee machine, not a hard job because the comforting sound of the coffee machine pulsing in the morning is etched into my brain. Coffee machine can't go anywhere without a fight, so I decided to try DC blockers as per Rod Elliots spec.
Hum is gone and my coffee has brighter highs with a clearer image, I can literally taste where in the field it was picked. Seriously though, DC blockers on amp, not on coffee machine.