Download and install the Elevayta Extra Boy VST-plugin or a similar plugin. Navigate to the VST-plugin directory on the hard drive and ensure that the .dll file has appeared. Launch the Multi-track host application and import the audio file.
Play the audio track to ensure it has imported without glitches or errors, then return the play head to the zero point at the start of the song. Click the effects insert button on the audio track. The appearance of this will differ, depending on the particular host application you have chosen. Mixcraft uses an "FX" button, Cubase uses an "E" button and Logic uses an array of blank slots. Click the button and insert and instance the Extra Boy VST.
Select the "Full-Spectrum" preset from the top toolbar and play the track. The "Full Spectrum" preset performs a high-resolution scan of the song and isolates the frequencies likely to contain the vocals. The vocal part should have been significantly reduced, if not removed all together. Try adjusting the "Center" and width controls to broaden the capture area of the plugin, which should help clean up any leftover vocal frequencies.
Select the "Export" or "Bounce" option from the "File" menu of the host application. Choose MP3 or .WAV file type and render the song to an external file, now minus its vocal part.