An electronic-drum module for connection to one or more electronic-drum pads is provided. The module includes an electronic display, a memory storing audio files for playback when the playback is triggered by a signal received from a pad, and one or more processors coupled to the electronic display and the memory. The processors are configured to play a portion of the audio files when the playback is triggered by the signal received from the one or more electronic-drum pads. The processors are also configured to display, on the display, a user interface for an application, which includes a waveform associated with recorded audio. The processors are also configured to display, on the display, tempo gridlines with a tempo-gridline spacing over the waveform. The module includes a control for adjusting the tempo-gridline spacing. The control is a wheel and is actuated by a rotation of the wheel.