C-D#/Eb-Gb/F#/A Diminished 4 STRING GROUPS E-D-G-B [E] [A] [D] [G] [B] [E] * * Eb * C * F# * * A * * * * * * * * * * F# * Eb * A * G C * * * * * * * * * * A * F# * C * * Eb * * * * * * * * * * C * A * Eb * * F# * * * * * * * * D-G-B-E [E] [A] [D] [G] [B] [E] * * Eb * C * * * * A * F# * * * * * * * * F# * Eb * * * * C * A * * * * * * * * A * F# * * * * Eb * C * * * * * * * * C * A * * * * F# * Eb * * * * * * A-D-G-B [E] [A] [D] [G] [B] [E] * * * * * * * * * A * * * C * * * * * * F# * Eb * * * * C * * * Eb * * * * * * A * F# * * * * Eb * * * F# * * * * * * C * A * * * * * * * * * * * * * E-A-D-G [E] [A] [D] [G] [B] [E] * * Eb * * * F# * * A * * * C * * * * * * F# * * * A * * C * * * Eb * * * * * * A * * * C * * Eb * * * F# * * * * * * * * * * * * * * * * * * * * * * A-G-B-E [E] [A] [D] [G] [B] [E] * * * * * * * * * A * F# * C * * * * * * * * Eb * * * * C * A * Eb * * * * * * * * F# * * * * Eb * C * F# * * * * * * * * A * * * * * * * * * * * * * I cannot overemphasize the IMPORTANCE of this incredibly useful finger formation for the guitarist! EVERY single form repeats at THREE FRET. MINOR THIRD intervals. No Exceptions. From a spelling point of view, it's worth noticing that all that has happened is we have taken the G natural, which is the fifth of the minor sixth, and lowered it one fret to Gb/F#, which is the diminished fifth interval of the C Mmi 6. However, there are four implicit synonyms all with the same fingerings! Thus this is also an Eb diminished, F#/Gb diminished, and A diminished. Which is also very important for practical chart reading. Again, your taste will dictate their applications in context. Some things will simply sound better than others in the course of applying these voicings to specific progressions and larger arranging contexts.