Spectrograph: Listen & Download Spectrograph .mp3 Error! Change your browser, please! ⇓ Download Lathe turning on, work, stop ⚠ Laser welding ⚠ Electric generator (hum) ⚠ Heidelberian sorting printer ⚠ Compressor industry ⚠ Air compressor turn on, turn off ⚠ Stamping press ⚠ Working machine engine ⚠ Electric welding ⚠ Factory work, general noise ⚠ Fluid drilling, Brewing unit ⚠ Postal sorting line ⚠ ★★★★★