Hi Leovigild,

The form that suits my fingers on piano, from the lowest now up, is 7th-3rd-13th (for the chord) and tonic for the bass. These are all the most characteristic notes in the chord.

I posted the above information for Shawn just as an example in case he hasn't been exposed to this kind of BIAB-thinking before.

That said, though...

As I understand theory (and there's always room for me to improve in this area)... The Bbmaj7/C can work if the Bbmaj7 bit is played in root position because that's the correct order of upper notes as the C13 is formed. Provided the bass C then sounds at least a minor 7th lower than Bb in the chord, the notes of the Bbmaj7 component are positioned correctly against the bass. This means that chord sounds as a root position extended C chord. Unfortunately, the chord is missing the third (E) that gives the major-key sound.

Load the style _SNOWDIN.STY (Snowed In Jazz Ballad w/ Horns), type in the below chord progression and have a listen.

F69 | Bbmaj7/G | BbMaj7/C | F69

BbMaj7/G = Gm9
BbMaj7/C = C13 (without the 3rd)

It's always fun playing around with this stuff smile

All the best,
Noel

MY SONGS...
Audiophile BIAB 2025