High pitch hum.

Question

Have a clip with a high pitch hum, which all parties did not hear on site, that showed up and cannot get rid of it. Tried Noise Reduction to the limit that all voices are distorted and hum is still there. Tried Effects -> Filter but no luck. Does anyone have an idea how to get rid of this high pitch hum. Wish there was a way to let anyone hear this audio.

Answer 1

I usually like to both see and hear what the problem frequency or frenquencies are in something like this.
If I were going to use EQ, I'd use Channel EQ and turn the Analyzer on, so you can see what frequency range there's a constant hum. In this case, it's a hum that also has harmonics, so one single frequency isn't going to get it. Using Channel EQ I dipped at two frequencies, around 500 hz and around 1khz, with a fairly steep Q, around 30. I dipped 500, -24 and 1khz -17, and that helped a lot.
To see at what frequency the hum is, Spectrum view works really well, too. When you see straight horizontal lines all the way across in the spectrum, there is your hum.
You could also try the noise reduction effect, but the EQ above really helped.
Good luck,
Matt