Spectrograph: Listen & Download Spectrograph .mp3 Error! Change your browser, please! ⇓ Download Mill for grinding grain, Brewing unit ⚠ Box making machine ⚠ Room noise, Glass bottles on a conveyor line ⚠ Hydraulic machine up ⚠ Car factory ⚠ Newspaper press ⚠ Hydraulic pump ⚠ Noise in, Grind wood with a grinder ⚠ Postal sorting line ⚠ Dry cleaning ⚠ Automatic telephone switch ⚠ Steam pump ⚠ ★★★★★