Chime provides you with a grid. Sometimes perfectly rectangular, other times broken up into pieces or segmented with unusable sections. Onto this grid you place a variety of different shaped pieces in an effort to form a three-by-three or bigger block. Stack more pieces onto a block and the block gets bigger, increasing score, coverage, and multiplier. Once a block's completed, the area it occupied gets covered, and when you reach 100% coverage you get to reset the level and start again.
The cleverness comes in with the music. Each level is a different track made by some of the biggest names in electronic music, from Moby to Philip Glass. As you play, a line reads the level, producing the music and finalising blocks. Your pieces generate the melody, and their coverage adds texture and depth to the piece. In theory. In reality, you're far too busy making blocks and watching the clock to pay attention to all this intelligent design.
It's only when you venture into the Free Mode that you can actually experiment. It's music-making by proxy: you're never directly able to play a note. Instead, you attempt to play the game in such a way that it'll come up with something different. It's like creating an Audiosurf level and then listening to it, and hoping it comes out good.
Except you're locked into the single song, so it will always sound good, while at the same time restricting what you can influence. And being limited to just six levels, Chime, while smart and interesting, feels like a demo for an as-yet unmade game where your music library provides the levels.