Duke Jordan’s song ‘No Problem’ was first released in 1960 on the excellent album ’Flight to Jordan’ under the title ‘Si-Joya’. The 1973 trio recording on ‘Flight to Denmark’ is worth close scrutiny for piano players because of its beautiful, economic approach.
‘No Problem’ is in the key of C minor (see ‘Nica’s Dream’ for discussion – Link). The piece is relatively straightforward harmonically but we can make some interesting observations.
The Am7b5 in bar 8 is a sister chord to the C minor tonic, in fact you could call it a C minor13. The temporary II – V – I beginning in bar 9 moves to the relative major of C minor (Eb) so the piece “brightens” for a few bars (nice trick).
The ’B’ section feels like a shift over to a temporary F minor key centre . The Ab7 in bar 29 is a “backdoor” II – V- I (Fm – Ab7 – G7) setting up the V chord that returns to the top. For more on the “Backdoor Cadence” check out the ‘Dominant Substitutions’ section here (Link).