4.1 Harmony and Voice Leading I

Now that we have all the building blocks of notes, rhythms, and chords out of the way, we can start to analyze music and the rules of putting pitch combinations together.

The way individual voices of a composition move from chord to chord is called voice leading. Back in the 17th and 18th-century, when writing music was becoming normalized, rules of voice leading came about to guide composers on how to create aesthetically-pleasing compositions. This era is considered the Common Practice Period (CPP), and describes the years roughly between 1650 (Baroque Period) to 1900 (Romantic Period).

When heeding voice leading rules, any composer (or AP Music Theory student!) must take into consideration the correct chord spelling, spacing, and doubling of notes in the chords. This way, voice leading can achieve linear smoothness and bring about the independence of voices.

In this subunit, we are focusing on the relationship between the soprano and the bass lines of a typical four-part harmony.

This is a chorale in four-part harmonies, composed by Johann Sebastian Bach.

If you look in the first measure, you see that all the stems of the notes on the top in treble clef are facing upwards. This is called the soprano line. The notes also on the treble clef, but below with the stems facing down, are all the alto line. Moving to the bass clef, the notes facing up are in the tenor line, and the notes with stems going down are the bass line.

Have you ever sung in a choir? Or at least heard something with a choir? The notes above correlate with the voices in a choir.

SATB for short!

Furthermore, in the chorale above, you can see the start of musical structure, with notes all leading to a fermata <hyperlink to Unit 2.13>.

When you see these fermati in four-part writing, you know you have reached a cadence, or the end of a musical phrase. Not all cadences have a fermata, but especially in J.S. Bach's writing, or other chorales, phrases are ended by fermati. We will go into depth about cadences later (hyperlink to 4.3), so don't forget this definition!

In four-part writing, the lineal movement between two voices can happen in four different ways:

1) Parallel motion: voices move in the same direction (both up or both down) by the same melodic interval.

2) Similar motion: voice move in the same direction but not by the same melodic interval.

3) Oblique motion: one voice remains still while the second moves up or down.

4) Contrary motion: voices move in opposite directions.

Using the above categories, the composers of 18th-century voice leading developed guidelines for writing music in four-part harmonies.

Good question. In the table below, remember that voice leading is how voices in one chord arrive at the next chord. Here is the beginning of the guidelines! Pay attention, these will get the money points on the AP free response questions 🤑.

In the AP Music Theory test, you will need to create a bass line to an established soprano line.

How do I create a rocking bass line in the CCP?

Now let's get back to looking at those four-part chorales.

There are different ways to categorize the spacing between voices on the staff. We consider them either open or closed positions.

In a closed position, all upper voices (soprano, alto, and tenor) are placed as close together as chord tones will allow. Any other spacing is considered an open position.

Closed position is on the left, and open position is on the right.

🦜 Polly wants a progress tracker: What are 3 guidelines to consider when writing a bass line from an established soprano line?