#AP Music Theory: Secondary Leading Tone Chords & Modulation - Your Ultimate Review 🚀

Hey there, future music maestro! Let's get you feeling super confident about secondary leading tone chords and modulation. This guide is designed to be your go-to resource for a last-minute review, so let's dive in!

#Secondary Leading Tone Chords

Remember how much we love the dominant function of V and vii°? Well, get ready to take that love to the next level with secondary leading tone chords! These chords help us create a stronger sense of tonicization. Think of them as the spicy version of your regular leading tone chords.

#What are they?

• Secondary leading tone chords (vii°/X) function just like regular vii° chords but in a temporary key.
• They usually appear as seventh chords: vii°⁷ and viiø⁷.
• In major keys, both vii°⁷ and viiø⁷ are fair game. In minor keys, stick to vii°⁷.
• Fully diminished seventh chords (vii°⁷) are more common.

#Example in B Major

Let's say we're in B major and want to tonicize the IV chord (E major).

• The leading tone in E major is D#.
• vii°/IV: D#-F#-A♮
• vii°⁷/IV: D#-F#-A♮-C♮
• viiø⁷/IV: D#-F#-A♮-C#

#Identifying Secondary Leading Tone Chords

1. Spot the Accidentals: If you see accidentals, it's a sign you might be dealing with a secondary chord.
2. Is it Diminished/Half-Diminished?: If yes, and there are accidentals, you've likely found a secondary leading tone chord. Remember, V chords are usually major.