You will find links to audio-files in a MIDI- and in a WAVE-format. The MIDI-files have a size of about 10 - 15 kB, the WAVE-files of about 300 - 500 kB. So it is recommended to use the MIDI-file if your system can play this.
Some songs have a link to a second MIDI-file, indicated by the icon. This is a version with larger formation. The sound quality of this file depends very much on the quality and the compatibility of your soundsystem.
The icon shows a link to sheets of (piano) music (GIF-Format, 1100x1600 pixel). If you are interested in more please contact firstname.lastname@example.org. They are available on different file formats for all Holy Songs.
MIDI-Files are made by Johannes Stampf; Web-Design: Paul J. Ettl