(Delaney Bramlett and Mac Davis)
From the Delaney & Bonnie album Accept No Substitute
Unlike Home, 1969's Accept No Substitute (also known as The Original Delaney & Bonnie) featured the same backing band on the entire album. The core of this band, which included Radle, Bobby Whitlock, Rita Coolidge, and Bobby Keys, would remain with Delaney & Bonnie for the rest of the year, touring England and the European continent in late 1969 and early 1970.
"Dirty Old Man" is kind of a modified twelve-bar blues with a bridge. (The first two verses are actually 13 bars each.) Radle's bass line is build largely on arpeggios. The root-3rd-5th-6th pattern is typical of a lot of blues songs, but this one is infused with an R&B groove. Instead of being a shuffle, which implies a triplet subdivision of each beat, the groove here has a sixteenth note subdivision. Radle plays essentially the same line for verses 1 and 2.
Radle uses lots of ghost notes to propel the song forward. Syncopations occur almost exclusively on beats 3 and 4. The following rhythmic pattern appears frequently in his line:
This is a common figure in R&B and soul music. In fact, it is not unlike the syncopation Radle uses in the choruses of "Piece of My Heart."
The bridge serves as a bit of relief from the repetition of the verses, but also allows the band to modulate up a half-step to C. Radle keeps the same type of 16th note syncopation, but his line sounds much more improvisatory than it did in the verses.
The outro is just a vamp from C to F. Radle continues his verse groove, but with added embellishments, particularly on the F chords.