His Cadd4 would be the Csus or Csus4 chord, same thing.

However, his Cadd5 would NOT be a C5 powerchprd. His guitar teacher is using this term to describe a particular inversion on the C, E, G stack of the Major chord. Most likely in first position on the neck, X,3,2,0,1,3 where that last 3 is the G on top. I do not know a way to force that particular voicing such that it would happen every time using a chord symbol entry in Band in a Box. This is because the particular Style file or Realtrack has a lot to do with the selected chord voicings.

"Cadd5" is technically not correct nomenclature for the type of chord described. There isn't a chord nomenclature in Fake Chording that would really describe this, so his teacher is likely simply using the Cadd5 for that reason, to describe for the student this above mentioned chord voicing.


--Mac