What Are Drop 2-4 Chords?
Drop 2 and 4 chords are created by dropping down an octave the second and fourth note of a seventh chord in close position. They can be very important tools for composition and arrangement. This lesson with diagrams provide useful explanations on how to build and play drop 2 & 4 chords on guitar.
What's a Tetrad ?
A basic chord is built with three notes this is what we call "triad chords" or "triads". Tetrad chords aka "four note-chords" are simply chords containing four notes, “tetra“ is a Greek root meaning four. This means that tetrads have an additional note, a major seventh or a minor seventh. In other words , a tetrad is a triad with a supplementary note. This article will enlighten you on how these tetrad chords are built and how they can be classified.
Here is a list of the main musical scales and modes.