The C4 Network uses a difficulty chart from Teaching Music Through Performance in Choir (2005, GIA):
| Level Number | Vocal | Tonal/Rhythmic |
|---|
| Level 1 |
- Short, simple vocal lines with limited ranges
- Conjunct vocal lines prevail
- Comfortable vocal range
- Manageable tessitura
|
- Major or minor tonality with little or no
chromaticism
- No modulation to other keys or tonalities
- Straightforward rhythms within simple or
compound meter
|
| Level 2 |
- Phrases of moderately challenging length
- Slightly disjunct vocal lines
- Brief, yet negotiable forays into extreme ranges
- Basic dynamic range
|
- Major or minor tonality with brief, obvious
chromaticism
- Brief modulations are obvious and move to closely related keys
- Modal passages
- Dissonances are approached and resolved by step
- Short passages of challenging rhythm within simple or compound metric structure
|
| Level 3 |
- Short passages requiring advanced vocal technique
- Some passages of challenging tessitura
- Long phrases requiring good breath
control
- Vocal melismas of moderate length
requiring martellato technique
- Wide dynamic range
- Extended crescendos and decrescendos
- Wide range of languages encountered
|
- Major or minor tonality
- Concrete or implied modulations to different tonalities
- Dissonance approached by leap
- Added note harmonies
- Imitative and non-imitative counterpoint
- Difficult rhythms may occur, but are usually repetitive
- Simply constructed mixed meter
|
| Level 4 |
- Long phrases requiring excellent breath control
Extreme Ranges
- Vocal lines requiring subtlety of shape, dynamics, and expressivity
- Long vocal melismas
- Alternative vocal techniques (i.e., non-Western techniques)
- Refined diction required as stylistic vehicle
|
- Extended modal passages
- Passages in non-diatonic harmony Frequent chromaticism
- Challenging rhythmic passages may be extended and non-repetitive
- Full compositions in mixed meter
|
| Level 5 |
- Vocal maturity required
- Extreme ranges required
- Repertoire at this level will provide numerous challenges for the experienced choral ensemble
|
- Atonal passage or passages of extreme dissonance
- Unprepared/unresolved dissonance harmonies
- Very complex rhythmic/metric structure
- Repertoire at this level will provide numerous challenges for the experienced ensemble
|
