What do the icons above a chart mean?
Each chart contains three icons above it. The left-hand speaker icon allows you to hear the chart according to your playback preferences (tempo,sound,click,loop). The other icon allow you to cross-reference this chart against the other remaining device. For example, if you are checking out a particular voicing for a C Ionian scale, you can find out which arpeggios sound good with this scale, and which inversions of these arpeggios overlap this particular scale fingering.
