Abersold books often show you the scale so you can see whether they mean the plus sign as 'sharp' or 'add', in context. Look at the song(s) where these occur, and they may have a few bars showing blowing scales.

This is why I don't use a plus sign.

Just guessing, I would probably pick C7#11 for the first, and C7#9 for the second. But who knows?

Which book? If I have it, I can give a better answer.


BIAB 2026 Win Audiophile. Software: Fender Studio One 8, Swam horns, Acoustica-7, Notion 6, Song Master Pro, Win 11 Home. Hardware: Intel i9, 32 Gb; Fender Quantom HD8 & Faderport 8, Royer 121, Adam Sub8 & Neumann 120 monitors.