Was wondering if that is suppose to remove sounds like a bad microphone reception kinda sound?
The High Pass Filter reduces low frequency sounds (high frequencies “pass through” the filter unchanged): http://manual.audacityteam.org/man/high_pass_filter.html
The Low Pass Filter reduces high frequency sounds (low frequencies “pass through” the filter unchanged): http://manual.audacityteam.org/man/low_pass_filter.html
This is what it sounds like.
I presume this is about the same thing as this topic: https://forum.audacityteam.org/t/using-audacity-for-psb-7-spirit-box-recordings/44298/1
so to avoid confusion I’ll lock this topic.