One of the exercises I give to my students to practise the triads is this one. I let them play the triads of Em, Am and Dm up and down the neck - bidirectional. While playing the triad on the G-B-E string they alternate also the bass note on the open E, A & D. So the open E while playing an Em triad, the open A while playing an Am triad and the open D while playing an Dm triad.
Some of you maybe noticed already that all the indicated notes above are the notes of the "A" Aeolian or "A" natural minor scale.
See : Aeolian Scale
written by Peter Bos
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