Draw your own bass line in the piano roll

Steps

1. Choose Help > Browse Demos... and open Midi Clip Synth. It plays a 16-bar loop in A minor at 138 BPM. Turn your speakers down a little first.

2. On the canvas, click the node named clip_player. The viewport shows its notes, and its card has Open the piano roll (E): click it, or press E. The piano roll opens: keys on the left, notes in the middle, each note's velocity under them, and five controller lanes at the bottom.

   

3. Press Space to stop or play. Press Cmd+A (Ctrl+A on Windows and Linux) to select every note, and Delete to clear them.

4. Draw your line. Click in the note area to add a note. Drag a note's right edge to make it longer, and drag the note up or down to change its pitch. Notes snap to the grid.

5. Play it in. Press Ctrl+K and your computer keyboard plays notes: A S D F G H J K are white keys, W E T Y U the black keys, and Z and X move an octave down or up.

6. Select some notes and press Q to quantize them onto the beat.

7. A filter sweep. In the CC74 Filter Cutoff lane under the notes, click points to draw the cutoff rising over the bars and falling back. Press Space to hear the synth open up.

8. Shape the synth. In the Objects panel, click synth_panel under Panels. The viewport shows the synth's panel: change Waveform, the Cutoff and Resonance, and the Attack, Decay, Sustain and Release of each note while it plays.

9. Keep your version with File > Save As....