[mikelevins]

You might like the Linnstrument:

https://www.rogerlinndesign.com/linnstrument

As a longtime guitarist myself, I found it quite easy to learn.

You can think of each row as a guitar string. In the default setup, each row is a perfect fourth above the row below. The green lights are the white keys on a piano; the unlighted keys are the black ones. The blue lights are C natural.

Skip a square diagonally up and to the right for an octave.

Chord shapes are uniform across the whole surface.

Keys are sensitive to pressure, left-right movement, and top-bottom movement. In the default configuration, rocking left and right yields vibrato and moving top-bottom controls some other MIDI parameter (usually filter cutoff, but it's configurable).

Sliding finger pressure to different keys to the right and left gives portamento. Sliding to the next row up or down gives legato.

Once you get used to these parameters, it becomes super expressive.

It's a MIDI controller, not a complete instrument, so you need a MIDI-controllable source of sounds. It's an MPE instrument, so, if you want the full experience, you want some kind of MPE-capable source of sounds (MPE is "MIDI Polyphonic Expression", and it means that multiple MIDI channels are dedicated to the instrument in order to give full, separate expression to each of several voices). MPE is a relatively new MIDI development that is not supported everywhere yet, so you have to pay attention to which sound devices support it if you want the full experience.

I have one; it's my favorite electronic instrument that I've ever tried. I also have an Eigenharp Pico, and I like it, but I like the Linnstrument better. (It doesn't look as cool as an Eigenharp, though :-).

When I decided to get one, I discovered that they're a bit hard to buy. Not very many places have them, and when I was looking, even Roger Linn didn't have any available. I eventually found one for list price at Detroit Modular (https://www.detroitmodular.com/).

[sleightofmind]

I watched the LinnStrumentalist video per your first link. Amazing stuff. And it does seem to reduce the amount of finger contortion required compared to most keyed or stringed instruments.

It does, though, seem to demand that the player look at the keyboard. For an instrumentalist, this may not be a big deal. For a performer accustomed to connecting to his audience with his face, as do many singers, it seems like a big drawback.

That said, color me amazed.

[mikelevins]

Yes, the Eigenharp is easier to play without looking, but I can say a couple of things about the need to look at the Linnstrument.

I've only had mine for a few weeks, but the need to look at it seems to be slowly disappearing. Now, the surface does feel really uniform, which is not so helpful for that. As you probably expect, there's not much on it that you can use to orient your hands by touch. Still, I do seem to be gaining some ability to know where my fingers go without looking. Partly it seems to be just acquiring a feel for how far apart the keys are (and you can feel the boundaries between keys). Part of it is starting to know which keys I'm touching from the pitches it's producing.

The second thing is that I've seen videos of players who attach a guitar strap and sling it over their shoulders (it comes with the attachments for that), playing it flat against their chests.

Taking those two things together, I'm fairly confident that it's possible to learn to navigate the keyboard by feel.

I haven't tried the over-the-shoulder thing, myself. So far, I play it on a table like a piano, or like a lap steel guitar or dobro.

I find it easy to learn, both comfortable, and expressive, and it's quickly become my favorite MIDI controller. I prefer it over both piano-style keyboards and MIDI guitars.