# Meantone add6-9 pentad

The meantone **add6/9 pentad**, or octave-equivalently the **add2/6 pentad**, is an essentially tempered dyadic chord in 5-limit meantone (81/80) tempering which tempers a 1-5/4-3/2-5/3-9/4 or 1-9/8-5/4-3/2-5/3 just chord in meantone. In letter notation, it is C-D-E-G-A, and each interval is a consonance if you count a major second as consonant, which it is in the 9-limit consonance set. It has subchords add2 (or add9) and add6, which are 9-limit just dyadic chords.