The LinnStrument 200 by Roger Linn Design is an 8x25 isomorphic grid controller that supports MPE (Multidimensional Polyphonic Expression). Unlike a traditional keyboard, the grid is tuned so that every row and column follows a consistent interval pattern. ChordColor visualizes chord shapes on this grid with two layout options: Perfect 4ths (each row is a fourth higher than the one below, like guitar strings) and Major 3rds (each row rises by a major third). The interval colors show the harmonic content of any chord shape across the 200 pads.
The key advantage of isomorphic layouts is that chord shapes are transposable -- the same finger pattern produces the same chord type regardless of where you place it on the grid. A major triad shape in C is identical to a major triad shape in F#. ChordColor makes this visible: the interval colors follow the pattern, not the absolute pitch, so you can see the shape consistency directly.
Connect your physical LinnStrument via USB and ChordColor can receive MIDI note data through the Web MIDI API (supported in Chrome and Edge). As you play on the hardware, the corresponding pads light up on screen with interval colors, giving you a visual feedback loop between your physical playing and the harmonic analysis. This is useful for learning new chord shapes and understanding the interval structure of what you are playing.