A Few Important Concepts
Reading and thinking about the following concepts will help you to better understand and play ChordMaps2.
ChordMaps2 doesn't generate sound on its own. It works by sending MIDI signals to other synthesizer apps, telling them which notes to play. (For those who are wondering, that's why ChordMaps2 isn't part of Audiobus, or InAppAudio, or Audio Units. It doesn't send out an audio feed.)
ChordMaps2 can send MIDI signals for notes played that are part of...
Chord Sound C1
Chord Sound C2
Bass Sound B
Melody Keyboard Sound M1
Melody Keyboard Sound M2
Additional Sound A1
Additional Sound A2
Display Keyboard Sound
At the beginning, and for simpler setups, it's often best to have certain sounds sending signals over the same MIDI channel. For example, the sounds C1, B, M1, and the Display Keyboard Sound, can all be set to MIDI channel 1. This will send the melody note, the bass note, the chord notes, and any notes played on the Display Keyboard all to the same synthesizer app playing just one of its sound programs.
When creating more complex setups using multiple synthesizer apps, the various sounds listed above can be assigned to their own separate MIDI channels.
What is the current key?
Which map is currently being displayed?
What is the most recent melody note touched or played?
What is the most recent bass note touched or played?
What is the most recent group of chord notes touched or played?
The melody note remembered is a single note.
The bass note remembered is a single note.
The group of chord notes, depending on the map and the situation, can be anywhere from one to four notes.
When a melody note is played, the melody note sounds, and it is also stored in memory. When a new melody note is played, the new melody note sounds, and the new melody note replaces the previous melody note stored in memory. The same principle applies to bass notes and chord notes.
There are some playable locations that replace only one note (for example, the melody note or the bass note), and there are other playable locations that replace the chord notes, or the bass and the chord notes together, or, in some cases, the bass note, the chord notes, and the melody note all at the same time.
There are some locations on the screen and on the maps that repeat the bass note or chord notes. When you touch these locations, the notes play that were previously remembered.
This can be useful in certain musical situations. For example, suppose the sound desired is a pattern that plays a bass note followed by a corresponding chord. This pattern can be represented as bass - chord - bass - chord. The screen can be set up so that when a location on the map is touched, the bass note and the chord notes are calculated, but only the bass note is played. The chord notes can then be played when a Repeat location is touched that plays the chord notes currently being remembered.
Some Repeat locations play the entire chord, and some play individual notes or groupings of notes within the chord.
Normally, when you touch the screen with just one finger, the sound will play when you touch the screen and stop when your finger is lifted off the screen. This works well for situations where each note (or each chord) is intended to sound separately.
However, if you play with more than one finger at once, making sure there is always at least one finger in contact with the screen, then the sounds are held over until the next melody note, bass note, or chord is played. This creates a more legato (or connected) style of playing.
There is also another legato option for situations where you would like notes to continue sounding after you have lifted your finger off the screen. This option is called HOLD, and it can be applied to either the Bass and Chord notes, or the Melody and Display Keyboard notes, or both.
Because ChordMaps2 sends MIDI signals to multiple channels (channels for chords, bass, melody, etc.), there are switches on screen that allow you to determine which sounds are playing at any given time.
In order for the Chord Sounds to play in the Chord-Playing Region, C1 or C2 (or both) must be on in row 2 (column 2 in Landscape mode), and C along the left edge of the Chordmaps Region (in the ABC Hold area) must also be on.
In order for the Bass Sound to play, B or B-12 (or both) must be on in row 2 (column 2 in Landscape mode). This will allow the Bass Keyboard to send bass notes.
If you would like chords played in the ChordMap Region to send both chord notes and bass notes at the same time, then B and C (in the ABC Hold area) must both be on.
In order for the Melody Keyboard to sound, one of the following must be true: either M1 is on, or M2 is on, or A1 is on in row 2 (column 2 in Landscape mode) and also enabled in the Melody Keyboard, or A2 is on in row 2 (column 2 in Landscape mode) and also enabled in the Melody Keyboard.
If you wish to add Additional Sounds (A1 or A2) to the Chord-Playing Region, then A1 or A2 (or both) must be on in row2 (column 2 in Landscape mode), and A and C must be on (in the ABC Hold area).
Copyright 2016 Stephen Mugglin
Although ChordMaps2 gets its name from the idea that chords can be represented on a "map," the second principle is equally important -- that the different states of mind a musician might be feeling are also represented as playable areas of the screen, so that if the desire is there to play melody notes, explore bass lines, experiment with chord progressions, switch to relative or parallel minor keys and then back to major later, change key centers at any time... all of these options are available.
ChordMaps2 can send MIDI information on more than one channel. This allows you, for example, to assign one synth or sound to the melody note, a second synth or sound to the chord notes, and a third one to the bass note.
Full size iPad or iPad Pro recommended
The Simpler Explanation
The Technical Explanation