is there such a thing as a diminished prime?

Question

for example if you were given the notes D-Db, would this be considered a diminished prime? or is it simply a minor second? and conversely is there such a thing as an augmented prime (ex. C-C#), or is this simply a minor second as well?

Answer 1

The sound of the interval is a minor second, but the way it is spelled is what determines its type and quality.

As in your previous question, B to the next higest Bb is a diminished Octave -- so its inversion by definition must be an augmented prime. Conversely your diminished prime would invert to an augmented octave.

Even though they sound like minor 2nds.

My students refer to them is "demolished" and "demented" intervals -- but I try to discourage that a little :-)

EDIT:

To the responders below --

While enharmonically you are correct, there are ample examples of diminished and augmented primes in the literature. These intervals are not a harmony issue but a counterpoint and voice leading issue.

I would point you in the direction of a wonderful Mozart piece -- "Rondo in a minor" for piano K. 511. Sustained soprano voice with a chromatic scale in the alto voice descending from the same note.

Answer 2

Sure, you can have a diminished prime, or diminished unison. It's exactly as you describe. But it's a little tricky to wrap your brain around it. The interval from D up to the Db below it is a diminished prime. (No, I didn't type that wrong...that's exactly what I mean) And yes, C up to C# is an augmented prime.

And of course, you can have compounds: D up to the Db ABOVE it is a diminished octave, etc etc.

A minor second might sound the same, but it's a different interval based on the way the notes are notated.

Answer 3

It is difficult to understand what you are asking. The interval from D to Db is a I-VII and more clearly notated as D to C#. This is the tonic and seventh of a major scale, which played is a dissonance. I've heard jokes about this illustrating two soprano saxes played in unison, but I cannot imagine this being an element of accepted theory.

Answer 4

Usually, those intervals are referred to as "minor seconds" for simplicity's sake.