• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Simple high-pass filter to cut below 20hz


2016-11-16 4:07 am
I'm having some very low hum in a tube preamp. I did some measures with RMAA and I see there's a high peak on very low frequencies... It goes from 15hz and goes high in 10hz.

Is there some simple high-pass filter I can build only for filter this low hum? A 20hz or even a 15hz hp filter would help. How can I do this?