My previous post about the 300B tube amplifier build was a breakthrough for myself. That was my first 300B amplifier build that by its nature is direct-heated triode. I read everywhere saying that 300B amplifier will always have small hum present at the output. Mostly when pairing with the speaker sensitivity above 88 db. My 300B amplifier was built intended to drive a headphone. It is also can act as pre-amplifier. I only can imagine the result will be small hum present and I should accept it.
But the result is worse than my expectation. The hum is not at the acceptable level, even with the volume control fully closed.
I think more than a month I tried to figure it out, and with the help of one of my friends, now this 300B amplifier is completely free of hum.
Yes, you are read it correctly. No hum at all, it is dead silent. Only great music.
