This tool lets you choose up to two chords in any key and then generates a list of scales that are compatible with the chosen chord(s). While this can be of use for improvisation over any chord progression, it specifically assists with two types of progressions. For rapidly changing chord progressions, it can help to reduce the number of changes in scale that the improviser must make by providing scales that are compatible across specific changes. For chord progressions that take a long time to change, the list of scales to use can help you to explore new and different harmonic possibilities and add color to your solos.Features: – Over 75 types of chords – A chord symbol index