Piano Theory Teacher (Russia), Degree -Lecturer in Musicology Music Piano, French Horn, Theory, Harmony Counterpoint, Theory, (03) 9499 1900. Online music theory for guitar players wanting to know the rules. Guitar lessons for the absolute beginner. Theory lessons for experienced guitar players. Tab, chord, and scale diagram explanations. Online and downloadable theory lessons for guitar and bass players. Information about the annual subscription. Read what people say about our music theory lessons for guitar and bass.