Music Theory Lesson
dim7 vs min7b5 Tones
dim7 (diminished 7th) chords are constructed with the 1st, b3rd, b5th, and bb7th notes of the major scale. bb7 (double flatted seventh) is enharmonically equivalent to the the 6th note of the major scale.
min7b5 (half-diminished 7th) chords are constructed with the 1st, b3rd, b5th, and b7th notes of the major scale.
Ddim7
This Ddim7 chord shape is constructed of 1 (R for root), b3, b5, and bb7.