Guidelines for Completing Part-Writing Assignments

Part writing, also called voice leading, emphasizes the importance of both horizontal lines and vertical harmonies.  Studying four-part choral music—that is, Soprano, Alto, Tenor, and Bass—helps to address the common problems that arise when writing for different voices.  While learning and analyzing part writing it is useful to review some of the best examples of harmonization: 371 Bach Chorales is a great reference and study tool to have.

Important rules for part-writing are as follows:

1.  The spacing between S, A, and T must not be more than an octave.  The space between T and B can be greater.

2.  Each voice must stay within its vocal range; that is S, C4-G5; A, F3-C5;

3.  Motion

b.  Avoid parallel motion, such as fifths and octaves moving in the same direction.

c. Try to avoid leaps by sixth or seventh, generally preferring stepwise motion over leaps.

4.  Doubling:

b.  try to double the voice in the bass or soprano when possible

c.  do not double the leading tone or the seventh

d.  in a diminished triad try to double the third or fifth

e.  it is okay to leave the fifth out occasionally, but not the third or the root

5.  Try to avoid voices crossing one another if at all possible

6.  Avoid using illegal dissonant intervals such as the tritone

Robert Kelley

1. 
   Fill in the Roman numeral analysis (if it's not given)
   
   • 
     If a figured bass is given:
     
     • 
       Determine the root of each chord
       
     • 
       Do not change the figures (If no figure is given for a bass note, a first inversion chord is not allowed above that bass note.)
       
   • 
     If the melody is given:
     
     • 
       For each melody note, determine the chords for which the melody note is the root, 3rd, 5th, (and 7th).
       
     • 
       Choose a chord that creates a strong progression from the previous chord.
       
     • 
       Choose a bassline that fits the chords and proceeds by contrary motion and/or parallel tenths with the soprano. (Also make the bass leap from root to root at cadence points.)
       
   • 
     If an unfigured bass is given:
     
     • 
       Determine all of the chord possibilities for each bass note
       
     • 
       Decide which one to use from the bass motion and cadence points.
       
2. 
   Fill in all four voices of the first chord.
   
   • 
     Check spacing
     
     • 
       The space between S and A should not exceed an octave
       
     • 
       The space between A and T should not exceed an octave
       
     • 
       The space between T and B does not matter
       
   • 
     Check vocal range
     
     • 
       S = C4 - G5
       
     • 
       A = F3 - C5
       
     • 
       T = C3 - G4
       
     • 
       B = F2 - C4
       
   • 
     Check doubling
     
     • 
       Double the root
       
     • 
       Never double tendency tones (leading tones and chordal sevenths)
       
     • 
       Doubling may have to be revised once the next chord is written
       
3. 
   Fill in all four voices of the next chord.
   
   • 
     Keep all common tones in the same voice, when possible
     
   • 
     Resolve all tendency tones properly (leading tones up by step and chordal sevenths down by step)
     
   • 
     Other voices move by step, when possible
     
   • 
     Check spacing
     
   • 
     Check vocal range
     
   • 
     Check doubling
     
     • 
       Double the root when possible
       
     • 
       Never double tendency tones (leading tones and chordal sevenths)
       
     • 
       Always double the bass note of second inversion triads and diminished triads (which may be used only in first inversion)
       
     • 
       Double the 5th or 3rd if doubling the root causes unavoidable parallel octaves or fifths
       
     • 
       Occasionally the 5th (but never the root or 3rd) may be left out of the chord entirely, because of voice leading considerations.
       
     • 
       In order to create the most smoothness in a progression, the 5th or 3rd may sometimes be doubled if it produces better stepwise voice leading without creating parallel octaves or fifths (or doubled tendency tones).
       
4. 
   Check the connection between the previous chord and the current chord
   
   • 
     Check that tendency tones resolve properly (leading tones up, sevenths down)
     
   • 
     Check for parallel and consecutive octaves and unisons between SA, ST, SB, AT, AB, and TB
     
   • 
     Check for parallel and consecutive fifths between all voices (P8, P5)
     
   • 
     Check for direct octaves and fifths between outside voices (H8, H5)
     
   • 
     Check for voice crossings and overlaps (especially between T and A)
     
5. 
   Repeat steps 3 and 4 until the exercise is complete.
   

• 
  Label everything: The key of the exercise, Roman numerals, completely figured bass, cadence types, chord functions, 6/4 chord types, non-chord tones, suspension types, and reasons for irregular doubling, not resolving leading tone properly, incomplete chords, not holding common tones, etc.