This Ableton tutorial walks through the fundamentals of Emit, a granular sample playback device, using a kalimba recording as the working material. The spectrogram at the heart of Emit displays all the frequencies in a sample simultaneously: time runs left to right on the X axis, pitch runs bottom to top on the Y axis, and brightness indicates loudness, with white representing the loudest frequencies and gray the quieter ones.
At the center of the spectrogram sits the emitter, which generates particles shown as blue dots. Each particle glides across the spectrogram and plays back whatever tiny slice of audio it passes over, a slice called a grain. Moving the emitter to different positions changes which frequencies and moments in the sample get played back.
The emitter's size is adjustable by dragging its corners, and its position can also be set numerically in the controls to the right. The Angle parameter controls the direction particles travel, so dragging it backward sends particles playing the sample in reverse. Width spreads the range of directions particles can fire from, and enabling Bipolar lets the emitter generate particles in both directions at once.
When particles reach the edge of the spectrogram, the Edge setting determines what happens. Bounce sends them back across the graphic, Wrap moves them to the opposite side, and Delete removes them entirely. Each option produces a noticeably different texture in the resulting sound.