thomann Millenium Drums MPS-150 User Manual page 18

Connections and operating elements
10 [USB]
Connection socket for USB cable.
11 [MIDI OUT]
Connection socket for an external MIDI device to send MIDI commands.
12 [OUTPUT – R / L/MONO]
Output for external audio devices (mono / stereo).
13 [AUX IN]
Input for external audio devices like MP3 or CD players.
14 [PHONES]
Connection socket for headphones.
MPS-150
18
E-Drum Module