Encoding Messages

Demo has a hidden message, try to decode it, the result may be cryptic. (No spoilers other than its a mystery) Character MIDI Note A C7 Base note B C7 (The sound is a bit quiet/is a sine wave than on other notes) C D7 D D7 (The sound is a bit quiet than on other notes) E E7 F F7 G F#7 H G7 I G#7 J A7 K A#7 L B7 M C8 Octave up N C8 (The sound is a bit quiet than on other notes) O D8 P D#8 Q E8 One octave down (C6) R F8 S F8 (The sound is a bit quiet than on other notes) T G8 U G#8 V A8 W A#8 X B8 Y C9 Octave up Z C#9 0 D9 1 D#9 2 E9 3 F9 4 F#9 5 G9 6 G#9 7 A9 8 A#9 9 B9 But anyway, a concept how you can encode messages in music.