Please evaluate this sample

Special Interest Groups Audiobook Production
12

There’s constant mains-hum and and intermittent metallic ringing at ~5Khz.
Those can be removed using this set of notch filters in Audacity’s nyquist prompt …

(setf *track* (notch2 *track* 59 5))
(setf *track* (notch2 *track* 119 10))
(setf *track* (notch2 *track* 4780 50))
(setf *track* (notch2 *track* 5050 50))
(highpass8 *track*  20)

what the code looks like in Audacity's nyquist prompt.png

[ Paul-L’s DeClicker plugin for Audacity is here … Updated De-Clicker and new De-esser for speech ]