Insert headphones into the headphone jack on the bottom-left side of the GX 4000D and microphones into the two microphone jacks on the opposite side. These connections are optional; you'll need headphones only if you want to hear the music without disturbing others and you'll need microphones only when you want to record.
Connect cables into both of the output connectors and run them to the appropriate connectors on an amplifier.
Connect speakers to the amplifier. This is the extent of a playback connection. From this point, you can play a recording through the speakers or through headphones.
Insert cables into both of the input connectors or the DIN connector and run the cables to the device from which you want to record. You can connect the GX 4000D to keyboards and synthesizers, workstations, such as devices in the MPC series, turntables or electric instruments.
Plug the power cables of each connected device into a power source.
Turn on each device to complete the procedure.