The Screen Explained - Part 1
The areas and zones on the ChordMaps2 screen are described here. (Portrait mode)
The Minus Sign takes the key down a half step.
The Plus Sign moves the key up a half step.
Choosing one of the letter names selects that key as the current major key. (When a minor map is selected, a lower case m will be displayed under each key name.)
Info opens a view where MIDI channels and destinations can be assigned.
Before looking at this row, it's helpful to consider the following ideas. Chordmaps2 works at any given time with just a few notes. In the most basic configuration, there would be one bass note, one melody note, and anywhere from one to four chord notes. When the time comes to send out the MIDI signals, the bass note information is sent out on the Bass Note MIDI channel, the melody note information is sent out on one (or both) of the two Melody Note MIDI Channels, and the chord notes are sent out on one (or both) of the two Chord Note MIDI Channels.
This row, the second row, contains a set of "switches" or "gates" that determine whether or not the MIDI signals are actually sent out on these channels. If C1 is "on," then chord note information will be sent out on the MIDI channel associated with Chord Sound 1. If C2 is "on," then chord note information will be sent out over the MIDI channel associated with Chord Sound 2. If B is "on," then bass note information will be sent out on the MIDI channel associated with the Bass Sound. If M1 (or M2) is "on," then melody note information will be sent out on the MIDI channel associated with Melody Sound 1 (or Melody Sound 2).
What this means in simple terms is that the buttons labeled C1, C2, B, M1, and M2 are like on/off switches. Turning any of these switches "on" allows MIDI signals to flow out over that particular channel. It's a little bit like the way a pipe organ works. You can press the keys on one of the pipe organ keyboard manuals, but no notes will sound unless at least one of the "stops" has been pulled for that manual. In this analogy, C1 and C2 are like "stops" that allow chord note information to be sent out to the synthesizer apps waiting to play chord sounds. B is like a "stop" for the bass sound, and M1 and M2 are like "stops" for the melody sounds.
The Octave - and + buttons at the far left can raise or lower the chord notes played in one octave increments.
The B-12 button plays the bass note one octave down. If B and B-12 are both on, it's like playing octaves in the bass, even though the user is tapping with only one finger.
The second set of Octave - and + switches, located about two thirds of the way across the row, applies to Additional Sound A1 and Additional Sound A2. These sounds are layered sounds. If A1 (or A2) is on, then this sound is available if the user would like to add it to the Melody Keyboard, or to the Chord-playing areas of the screen.
The box labeled "Name" is a display location showing the name of the most recently played chord.
All Notes Off sends note off commands (actually sends note on commands with velocity zero) to every synthesizer listening. This is designed to turn off all the sounds currently playing. (Some of the synth apps we've tested have gotten into states where they don't respond to this button, and we had to double-click the home button on the device and turn off that app, but most of the synth apps will silence all playing notes when this button is touched.)
The Display Keyboard not only gives a visual indication of the notes currently being played, but it is also a playable region. Besides the GL and MM switches, located at either end of the keyboard, there are 24 zones across the Display Keyboard that are assigned to play individual chord notes. This note information is sent out over the Display Keyboard MIDI Channel. (Note: the Display Keyboard does not have a switch acting as a "stop." It stays on (except for the MM case described below), so if you have assigned a synthesizer to respond to the Display Keyboard MIDI Channel, that synthesizer will sound when the Display Keyboard is played.)
GL, located at the left edge, turns on the Glissando function. When Glissando is on, many of the playable regions on the screen can be glided over, and all the locations will sound as they are touched. (Note: the ChordMap Region, where the chord progression maps are played, does not respond to Glissando playing. It is designed so only one chord will sound at a time, and sliding off a chord by mistake will not accidentally trigger the adjacent area.)
MM, located at the right edge, turns on "Mirror the Melody." This means the Display Keyboard will no longer send out MIDI signals on the Display Keyboard MIDI Channel. Instead, the 24 zones mapped out across the Display Keyboard serve as an extension of the Melody Keyboard. Touching the Display Keyboard causes Melody Notes to play just as they would when playing the Melody Keyboard, but the notes that sound are limited to chord notes, and they may be higher or lower across the 88 note range.
The Melody Keyboard is designed to be played just one note at a time. It is a transposing keyboard, meaning the user can play the major scale on the white notes, starting at 1 and going up to 7, regardless of which key is currently selected at the top edge of the screen. (If it is desired to play the keyboard without the transpose function enabled, it can be turned off at the left edge of the Bass Keyboard, located at the lower edge of the screen.)
The Octave + and - buttons shift the Melody Keyboard up or down in one octave increments.
The M-12 button adds the note one octave below the current melody note being played.
The A1 and A2 buttons add the Additional Sounds as layered sounds (if the A1 and A2 switches at the top are also enabled.)
The H M1 and H M2 areas on the far left, and the H A1 and H A2 areas on the far right have a special function. If the M1 switch is on in row 2, and if the H M1 area is also on, then the single melody note played will send not only the melody note, but also harmony notes that fit in with the most recently played chord. (Note: the melody note played may or may not be part of the current chord, but the harmony notes added will be.) This allows any melody note to be harmonized by the most recently played chord.
The same applies to H M2. If M2 is switched on in row 2 and H M2 is on, then melody information sent out over the Melody Sound 2 MIDI Channel will add harmony notes to the melody note being played.
Similarly, if A1 (or A2) is switched on in row 2, and if A1 (or A2) is also enabled as an added layer in the Melody Keyboard, then the H A1 and H A2 locations can be used to add harmony notes to A1 (or A2) when melody notes are played on the Melody Keyboard.
Copyright 2016 Stephen Mugglin
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The Simpler Explanation
The Technical Explanation