What is Stretch?Video Lesson – The Difference Between Pure P12 and Pure P19The Go A.P.E. Aural Piano Tuning Stretch Sequence for Producing the Most Number of Pure IntervalsWindows Sequence for Tuning Accurate Stretch – PDFWhat intervals take priority where? – PDF
Have you seen the Piano Theory book?
It's loaded with figures, diagrams, and cool piano theory discussions.
