Tricotism: Oscar Peterson’s approach to “non-dominant” dominant 7ths

The following examples are from Oscar’s solo on The Sound of the Trio, recorded live in Chicago in 1961. https://youtu.be/2jL_Kg-lS_k

Eb7, in the context of the key of Db major, is generally understood to have a “lydian-flat-seventh” sound, and is traditionally interpreted (though rarely taught) using the one-chord of the scale in which it appears, the tonic of Bb melodic minor, BbmM7.  This is indeed Peterson’s preferred approach.

These are the basic changes to Tricotism with the chords we’ll be exploring in boldface:

Dbmaj7  | Dbmaj7  | Eb7    | Eb7    | Gb7   Gdim7     | Db   Bb7   | Ebm7 (A7 in the head)  |  Ab7     |  

Dbmaj7  | Dbmaj7  | Eb7    | Eb7    | Gb7   Gdim7     | Db   Bb7   | Ebm7   Ab7   | Db      |

A7      |  A7     | Dbmaj7  |  F7        | Bbm    Bbm(M7)  |  Bbm7    Bbm6   | Ebm7     | Ab7   |

Dbmaj7  | Dbmaj7  | Eb7    | Eb7    | Gb7   | Gdim7     | Db   Bb7   | Ebm7   Ab7   | Db      |

The examples are from the first four choruses of his solo. The numbering of the examples refers to the chorus (numbers 1 - 4) and the eight-bar section (a - d) within each 32-bar chorus. Thus “Ex 3(c)” would refer to what Oscar played over the A7 in the bridge of the third chorus. Please disregard any stray measure numbers - I just forgot to remove them from the finale file!

I’ve asserted in other posts (and still believe) that we play and hear jazz on a number of levels, sometimes simultaneously. In other words, it’s possible to be “in Eb7,” use Bbm gestures to play over it, and do so in a way that emphasizes the home key of Db. That is precisely what is happening in many instances here. 

            

                              Ex 4(d)

The use of blue notes is a reliable indicator of tonicization, that is, the improvisor’s conception of the tonal center at a given moment. In Peterson’s Tricotism solo, Fb’s (especially those leading to F-natural) are best understood as being blue thirds in Db, rather than the b9 of Eb7. I strongly believe that this is also how our ears perceive it.

                    Exx 1(a) and 4(a) 

                                               

Another blue third, in example 3(b), is an Ab in an upward F-Ab-A-C run, may not be heard as such - indeed it fairly flies by - but still indicates Oscar's investment in the F-major triad implied by the upper chord tones of a Bbm(M9) chord.

                       Ex 3(b)

In the first two choruses Peterson seems to be studiously avoiding the major third G of Eb7, preferring to play Bb-melodic minor passages, or reference the home key of Db with blues gestures. But as we saw in the previous example, starting with the third chorus a bit more attention is being paid to the "written" changes.

                       Ex 3(d) 

His approach to A7 is more enigmatic; he never “spells” an A7 or A9, preferring to arpeggiate Em7 or Em9. 

                        

                         Ex 2(c)

In the following examples, he seems to hold off as long as possible from the major third C#, which he never approaches by means of a blue third. Indeed this note appears to be the target note of the run, but sounds like neither a resolution or the home key tonic. Maybe Oscar's fingers recognized a Db?

 Exx 3(c) and 4(c)

In general, Oscar is playing in a very clear, chord-specific manner. But the chords he prefers to be specific about are substitutes rather than the written ones.

Following are all the examples from the first four choruses.