Why are major seventh chords called delta chords and written with a delta symbol, like CΔ7 or CΔ? Do engravers consistently use Δ to mean a seventh chord (such that Δ7 is redundant) or do some use Δ ...
A dominant 7th leads to a major 6th and a major seventh leads to the tonic, but what does the note in between the two lead to? If you could tell me what the maqam rules for that are, that'd be fine, ...
The tonic's seventh is both the seventh of the chord and the leading tone of the scale. So what should happen with this seventh if it needs to be raised or lowered?