http://eeiia247v5pnz76wraeusfdvfmi2fkdf7zqve6txpmafknnanqgjxnyd.onion
Anything under 20 Hz is (R-F), and anything
over 20,000 Hz is (U-S). One example of this is the programs: Equalizer APO and Peace Equalizer
GUI. These programs of which cannot generate or test audio frequencies below 20 Hz, as they are
designed to work within the capabilities of standard audio hardware and software.