Beat Blocks is a tangible interface for a rhythm sequencer. The user is able to create and manipulate an 8-track drum loop (4 tracks in the featured prototype) on the fly by physically re-arranging blocks within a matrix. Each block is actually a sub-sequence identified by a patterning scheme. This allows the user to quickly identify what the sub-sequence is and place it within the composition in one motion, an action that would otherwise take several steps with a screen and mouse/trackpad interface. The device can be integrated directly and synchronized with other midi hardware or communicate with a computer via midi.