The Kelstone is a stringed instrument, 9 strings tuned all the way in fourths.
The essence and innovation of the Kelstone is not so much that it is a tapping instrument but that the strings and hands lie in front of the player. This position gives the hands a lot of new opportunities and control over a string for expression and harmony.
In that sense the Kelstone has actually 1 string, 9 times. It makes a big difference.
Because of the new freedom of movement (compared to stringed instruments where the hand goes round a neck), one can make extreme and very subtle slidings and bendings and have a total new control over the sustain and the envelope of a note.
It’s the same reason why Les Paul & Leo Fender (Jimi Hendrix), Adolph Sax (Charlie Parker), and Laurens Hammond (so many) where so important to music and expression: prolonguing one (or two or three) notes, being able to raise the volume after hitting it (them) and controlling it (them in a new way).
If you want to hammer on strings, this is an instrument especially designed for it but any technique is possible: strumming, fingerpicking, hammer-on, pull-off, sliding, bending, use harmonics, etc.
You have a total range of 5 octaves and 3 whole notes.
Two fingers can overlap almost 4 octaves and all the notes in between.
Chords and scales have the same figure in any key, regardless of the position on the neck (26 frets).
As on the piano, you can assign bass and melody/chords to different hands.
It has also a patented muting system that give quite a unique sound.
Basically and literally one views a string from a different angle.