# Jazz Theory for Orchestral Musicians, Music theory

Extended chords, chord-scale theory, and the ii–V–I

Jazz harmony has infiltrated every genre of contemporary music. This module teaches extended chords, chord-scale relationships, jazz scales, and the ii–V–I progression, with examples from Wynton Marsalis and Mark O'Connor.

Maestro · 5 lessons · approximately 140 minutes of material (not a mastery deadline).

## Before this module
- [Introduction to Post-Tonal Theory](/learn/theory/post-tonal), Atonality, twelve-tone technique, and pitch class sets

## What this module covers
1. **Extended Chords in Jazz**, Major 7, dominant 9, minor 11, the jazz chord vocabulary (28 min)
2. **Chord-Scale Theory**, Matching each chord to its scale, the jazz improvisor's map (28 min)
3. **Jazz Scales**, Blues scale, Dorian, Lydian dominant, and altered scale (28 min)
4. **The ii–V–I Progression**, The fundamental harmonic unit of jazz, and why it works (28 min)
5. **Jazz Harmony in Modern String Writing**, Marsalis, Mark O'Connor, and the jazz-classical intersection (28 min)

## Practise with a free reference
- [Public scale references](/learn/scales), Read pitch sequences and play reference examples. Available routines do not establish an exam syllabus requirement.

## What comes next
- [Improvisation & Ornamentation in Classical Style](/learn/theory/improvisation), Baroque ornaments, figured bass improv, and cadenza writing

## Where should I start with jazz theory for orchestral musicians?
The curriculum places Introduction to Post-Tonal Theory before this module. Review those topics if they are unfamiliar. The first lesson is “Extended Chords in Jazz”: Major 7, dominant 9, minor 11, the jazz chord vocabulary. The order is a study guide, not proof that every learner needs the same pace.

## How long is the jazz theory for orchestral musicians module?
The 5 listed lessons total approximately 140 minutes of material. That estimate describes lesson content, not the practice time needed to become comfortable with extended chords, chord-scale theory, and the ii–v–i. Revisit one task at a time and use feedback from a teacher where physical technique is involved.

## What can I try here without an account?
The jazz theory for orchestral musicians description, lesson sequence and prerequisite links are public. There is no full worked lesson sample for this module yet. The linked public tools and references are free. A free account includes the complete five-lesson foundation module in each instrument and five lessons in music theory, with saved progress and no expiry. Later lessons require the relevant paid package.

## Continue in Arco
The complete five-lesson foundation module in each instrument and five music theory lessons are free with an account, including saved progress and no time limit. Later lessons require the relevant paid package. Public samples do not assess your physical technique or certify exam readiness.

[See packages and pricing](/pricing) · [Back to the music theory curriculum](/learn/theory)

Canonical source: https://arcosounds.com/learn/theory/jazz