Mr. Jackson
AP Music Theory
We’ve Seen This Before…
Let’s Take a look at some of the last slides from Unit 5 …
Part Writing Textures
 4-PART TEXTURE
1. All members of TRIAD are present. The final I chord can
be incomplete with a 3rd and tripled root.
2. The ROOT is usually doubled. (The leading tone – 7th
scale degree – is almost NEVER doubled.)
3-PART TEXTURE
1. The 5th of the TRIAD is often omitted.
2. An incomplete TRIAD will usually have a doubled root.
(The leading tone – 7th scale degree – is almost NEVER
doubled.)
 We will almost always look at 4-part texture.
Introduction to Part Writing
 When studying harmony, we often will see a four-voiced texture called
chorale style. Two goals define this style:
INDEPENDENCE OF VOICES &
DEFINITION OF TONALITY
Voice leading controls the relationship between voices.
 There are rules concerning doubling and chord voicing.
Part-Writing Voices/Stems
 When constructing chords vertically for part writing, we use four voices.
 The name and ranges of these voices are derived from the four standardized
singing ranges
 SOPRANO
 ALTO
 TENOR
BASS
 SOPRANOS/ALTOS are placed on
the TREBLE CLEF of the grand staff
 TENORS/BASSES are placed on
the BASS CLEF of the grand staff
 SOPRANOS and TENORS have STEMS UP
 ALTOS and BASSES have STEMS DOWN
This is what it looks like…
 Notice there are four distinct lines. Your ear can follow all of them!
7 Rules of Part Writing

RULE ONE – SPACING IS AN ISSUE
 The SOPRANO and ALTO must be within one octave of each other,
 The ALTO and TENOR must be within an octave of each other.
Therefore, the SOPRANO, ALTO, and TENOR have an available range of 2 octaves.
 It does NOT matter how far the TENOR is from the BASS.
Don’t be afraid to write the Tenor above C4 – they can handle it!
Both are OK!
7 Rules of Part Writing

RULE TWO – WRITE FOR FOUR DIFFERENCE VOICES
 The BASS LINE is always given to you. You DO have the freedom to decide what
OCTAVE your bass moves in after the first chord.
 The BASS line is the most disjunct (moving by skips and leaps) of all voices.
 The SOPRANO LINE always has the melody, and is conjunct (moves mostly
stepwise).
 Most frequent endings are Mi-Re-Do or Re-Ti-Do.
 The ALTO and TENOR voices are as static as possible – moving very little!
7 Rules of Part Writing

RULE THREE – KNOW THE VOCAL RANGES AND STAY WITHIN THE “HEART”
OF EACH RANGE
 Keep it Simple: The SOPRANO and TENOR range is from C to G.
The ALTO and BASS range is the opposite: G to C.
 Although we realize the soprano can and most certainly DOES sing above a G5, she
doesn’t have to! Taking her up to and A is certainly acceptable – much higher is just
not necessary. Try and stay within this range, knowing each voice has at least a
whole step in either direction for extreme range.
7 Rules of Part Writing

RULE FOUR – DOUBLE THE ROOT 1ST, THE 5TH SECOND, AND THE 3RD WITH REASON
 If you have a TRIAD and FOUR Available Voices, one chord member is usually doubled.
 In ROOT POSITION, DOUBLE THE ROOT when possible
The exception is V-vi(VI) – usually double the 3rd in the vi(VI) chord!!!!!
 In FIRST INVERSION, try to DOUBLE THE SOPRANO unless the leading tone is
present there.
o If that doesn’t work, DOUBLE THE BASS; then anything else.
o In first inversion diminished triads, DOUBLE THE BASS!
 In SECOND INVERSION, DOUBLE THE BASS.
 In order to properly resolve the leading tone, and in cases of extreme part-writing
difficulty, you may TRIPLE THE ROOT and INCLUDE THE 3RD (omitting the 5th.)
NEVER OMIT THE THIRD as it dictates chord quality!
 Never double the leading tone in major OR minor keys! (Tendency tone – Ti to Do)
 Never double the 7th of a seventh chord (It is a tendency tone – Fa to Mi)
V to VI Exception
7 Rules of Part Writing

RULE FIVE – DON’T CONFUSE THE EAR
 Never cross voices. This means you cannot write the soprano voice lower than the
alto, or the alto voice lower than the tenor voice.
 It confuses the ear because it cannot separate the lines. Remember the goal is
to write four distinctly separate lines.
 The most common problem with this issue occurs between the ALTO and
TENOR voices.
 Never overlap voices. This simply means that you don’t want to write one voice
higher than another voice has been in the previous chord.
In the excerpt above, we not only have overlapping voices, but we have PARALLEL
OCTAVES between the bass and alto.
Oh, you didn’t know that was bad? We haven’t gotten to that rule yet.. Trust me! It’s bad! 
When voices overlap, you have one (or in this case two) of the voices taking over the
“character” or role of another voice.
Looking at the example, the soprano is clearly singing in ‘ALTO TERRITORY’ if you
will, which creates an identity crisis! See a similar problem with the bass line?
Although the bass line is usually defined for us, we still have control over what octave to use!
7 Rules of Part Writing

RULE SIX - RESOLUTIONS
 There are THREE rules of resolution. Memorize them and learn to apply the
concepts.
 RULE 1: IF V (v) goes to I (i) or VI (vi), THEN Ti resolves upward to Do.
 RULE 2: IF viio / viio7 OR V7 goes to I (i) or VI (vi), THEN Ti resolves to Do
AND Fa resolves to Mi.
 RULE 3: IF you have a seventh chord of ANY kind, THEN:
The 7th of the Chord resolves DOWN (or HOLDS until it can) &
if it’s a V7, the LEADING TONE of the chord (the 3rd ) resolves UP!
 If the LEADING TONE is present in an OUTER VOICE (Soprano or Bass); then it
MUST resolve UP to TONIC!!
(If in inner voices, it can resolve down a 3rd.)

7 Rules of Part Writing
RULE SEVEN – NO PARALLEL 5ths or OCTAVES!! / MOTION ISSUES
 The most egregious error in part writing is to have PARALLEL FIFTHS or
PARALLEL OCTAVES between two voices.
 The reason is a linear one. Parallelism confuses the distinction between the
four independent voices or lines, particularly when you have PERFECT
parallels.
 When any two voices move in the same direction at the same interval, they
sound as one, giving us three voices instead of four.
 BE WEARY OF PARALLEL MOTION!!
 CONTRARY MOTION occurs when two voices move in the opposite direction.
 SIMILAR MOTION occurs when two voices move in the same direction, but at
different intervals.
 OBLIQUE MOTION occurs when one voice remains on the same note and the
other moves in either direction.
 STATIC MOTION is your friend, occurring when voices remain on the same pitch.
**ALWAYS TRY TO HOLD THE COMMON TONE!!**
Types of Motion (Still Rule 7 People!)

In addition to parallel fifths & octaves, there are other types of parallels that should be avoided:
 Avoid HIDDEN PARALLELS/DIRECT PARALLELS – where two voices move in the same
direction to perfect intervals . Commonly found in outer voices (soprano and bass). Some
theorists think that such motion, especially in outer voices, creates the effect of perfect
intervals.
 Beware of UNEQUAL FIFTHS – where P5ths to d5ths or vice versa, are found in chorale
harmonizations and may be used sparingly.
 The progression viio6 to I, under certain circumstances, requires the use of unequal
fifths.
 Be careful when resolving the tritone in the V7 chord to avoid unequal 5ths – the
motion from the diminished 5th to a perfect 5th, especially in the soprano-bass pair. If
you resolve correctly, this will not occur.
 No voices should contain leaps of augmented intervals, any 7ths, or leaps larger
than an octave.
 Leaps of P5 or larger are best left in the direction opposite to the leap.
 Consecutive leaps in the same direction must outline a triad.
Part Writing for Second Inversion
Triads
 In a four part texture, the bass (5th of the chord)
should be doubled.
 The other voices generally move smoothly—often by
step, both into and out of the six-four chord.
 All members of the chord must be present.