In this topic I wish to gradually demystify modes, keys, chords, progressions etc. on the OP-Z master track. I am aware that information about music theory is widely available, but a lot of it is focused on guitars and/or much to dense for my limited span of attention. So here is what I found out, and on the bottom are some questions for you to answer and complete the demystification process for all.
- Take an empty project (shift+project+stop to clear a project) and go to the CH track.
- Make the note length 1 (hold track while turning green knob).
- Enter the triad C-E-G on the first beat (hold the first beat button and press the notes in sequence).
- Connect to the app and head to the Master track.
First conundrum: you entered just about the most basic chord there is: the C major chord. But OP-Z thinks you are in the key of F and in C mixo (short for mixolydian) mode and there is a dial with an F on top with a sub dial pointing to V (roman numeral 5). Your OP-Z keys are lit and show C D E F G A bflat C.
OK, so I found out what this means and it took some digging, so I thought I’d share.
- the mode name is equivalent to a roman numeral. There are seven modes, each with a pretty name, but also just a number.
- the modes are easiest to understand if you play the notes on the keyboard: the first mode is Ionian and starts at C. That could be written down as C-i (roman numeral i). Play the same notes from the D key and suddenly you are playing in another mode: D-ii or D dorian. Etcetera gives you all seven modes (just don’t go to the black keys. There be dragons). I got this from this excellent walk that bass tutorial.
- if you press a single key on the OP-Z you will transpose the song AND change its mode (and possibly its key).
- if you press a single key that is lit, you will only change the mode. If you press an unlit key, you will change the key too.
- if you play triads (with the root note at the bottom), you will be able to force the mode and change the key accordingly.
- you can force ionian mode by entering a C-E-G-B chord. Then you will get the C key.
How is this useful?
- if you play any of the notes that are lit in a lead, it will sound harmonious if you don’t change the key.
- if you want a pleasant and simple progression, use a single finger to transpose the song and stick to the lit keys.
- if you want more interesting stuff, go wild.
- you can get a lot of the basic chord progressions with very little effort. But if you want anything more interesting (suspended, augmented, etc) you are on your own.
- the fact that this can be sequenced makes OP-Z into a powerful tool for accompaniment. Added to the tilt-to-mic feature and this is a singing practicing dream.
- Why does OP-Z assume you want mixolydian F when you enter a Ionian C chord? Is it because of AC-DC songs (those apparently all are in mixo mode)?
- why does the mode have a name in the label on the right, but a number in the dial? Would it not have been more friendly to use the numerals everywhere (and switch to letters when there is a deviant)?
- what does a * mean next to the mode name?
- where to go from here?
- how does the OP-Z dial relate to thecircle of fiths? I see that it is similar, but what’s up with the rotating of the dial and the needle?