Musical Composition, Theory and Songwriting/2-5-1 progression


QUESTION: I saw a 12 bar blues (key of Bb) with a G7 in bar 8 and Cm7 in bar 9. G7 is a secondary dominant of Cm. If I'm correct this is also a 2-5-1 without the 2 chord. All 2-5-1 would therefore include a secondary dominant? Is this a correct understanding of jazz theory?

ANSWER: Hello Hank and thank you for contacting me through

Not all 2-5-1s include a secondary tone center, but they often do. These are added for color & diversity.  When the 6 chord (G7 in this case) is used, it is often referred to as a turn-around.  The G7 is dominate to C, but when you get to C it is a minor, thus it becomes the 2 of Bb making this secondary progression (cadence) false or misleading. Most progressions are in fact false or misleading.

Here is a helpful chart in the key of C:

Thanks for the interest.

D C DowDell
Professor of Music

---------- FOLLOW-UP ----------

QUESTION: So it's the first two chords of what jazz theorists call a  6-2-5-1 progression?
In order to create a 6-2-5-1 you just take a 2-5-1 but add a secondary dominant of the 2 chord?
Am I correct?

Yes, that is correct but be careful not to get too occupied with the terminology. Be more focussed on how it all sounds and how the chords change the direction of the harmony. That's what it's all about.

Thanks again,
D C DowDell  

Musical Composition, Theory and Songwriting

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D C DowDell


D C DowDell will answer questions about Jazz improvisation, composition, chord voicing, scales and modes, practice techniques and ear training. Professor DowDell also enjoys discussions on Jazz musicology and the evolution of style.

D C DowDell is a professional Jazz pianist/composer who currently teaches online Jazz studies at A Passion for Jazz!. Professor DowDell has been teaching music for over 30 years at 2 major universities, several community colleges as well as accepting students for private study.


American Federation of Musicians
National Music Teachers Association
International Association of Jazz Educators

Bachelors of Music Education from UCLA
Masters of Music Composition from UNT

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