The Naada instruments are both Mono and support Duophony.
Mono/String/Poly is the "Play Mode" of the keyboard and is not related to the polyphony instrument in the preset.
- In "Mono" mode you can only play one note at a time. For MIDI Out, Mono mode corresponds to MIDI mono mode.
- In "String" mode you can only play one note at a time for each row. Because the row is mono (like a guitar), you can use the HOPO gesture (Hammer On, Pull Off). For MIDI Out, "String" mode corresponds to MPE, MIDI Mode 4. It's also known as Channel-Per-Row.
- In "Poly" mode you can play more than on note per row like a conventional keyboard. However the HOPO gesture is not possible. For MIDI Out, "Poly" mode corresponds to MIDI Mode 3. It's also known as Channel-Per-Note.