Lumatone mapping for porcupine
Ultra-compressed
This has the largest range of any mapping shown here (5 complete octaves), but the sequence of nearby pitches can be confusing. In particular, notes separated by the Porcupine[7] chroma (denoted by ^/v here) are not mapped to adjacent keys.
Compressed
This is a compromise intermediate between the "ultra-compressed" and "expanded" mappings. It covers 4 complete octaves, and the Porcupine[7] chroma is now mapped to adjacent keys in the "vertical" direction. The sequence of pitches is still not completely intuitive, however: the Porcupine[15] chromatic scale still zigzags back and forth leaping over keys, rather than proceeding in mostly the same direction. This is because the Porcupine[8] chroma (denoted #/b on Porcupine Notation - for example the notes A and Bv are separated by this chroma) is still not mapped to adjacent keys.
Expanded
This mapping has the smallest range of any presented here - less than 4 complete octaves - but its main advantage is mapping the Porcupine[15] scale to an intuitive zigzag pattern. In-between pitches always appear in-between on the keyboard, rather than off to the side.