Standard, Baritone, or Bass Dulcimer Tuning

I know the tuning of the standard dulcimer is usually D-A-A or D-A-d, but at what point does the standard dulcimer become a baritone dulcimer?  I think most dulcimer players would consider a tuning one step lower (C-G-G or C-G-c) to still be a standard dulcimer tuning.  So dulcimers tuned to play in the Key of C and D would be considered as tuned to one of the standard tunings.

When the tuning drops down to A-E-E/A-E-a and G-D-D/G-D-g it is generally considered to be a baritone tuning, but where does the change take place?  Likewise, dulcimers tuned to play in the Key of G and the Key of A below the standard would be considered baritone dulcimers.

So, at what point is the tuning no longer considered a standard tuning and become a baritone tuning?  Likewise, as you continue to go lower in pitch when does baritone tuning change to bass tuning?  I have bolded those dulcimer tunings that are generally accepted as standard, baritone, or bass tunings.

Key of D Standard (D-A-A and D-A-d Tuning)

Key of C#/Db Standard

Key of C Standard (C-G-G and C-G-c Tuning)

Key of B 

Key of A#/Bb 

Key of A Baritone (A-E-E and A-E-a Tuning)

Key of G Baritone (G-D-D and G-D-g Tuning)

Key of F#/Gb 

Key of F  

Key of E 

Key of D#/Eb

Key of D  Bass (D-A-A and D-A-d Tuning)