Always check the internal fuses (usually 2 x 20A or similar) before installation.
If you are looking for specific repair information or wiring diagrams, several repositories offer PDF downloads:
To bridge channels 1 and 2, typically use the first positive (+) terminal and the second negative (-) terminal from the left.
According to technical data from amp-performance.de and Radiomuseum , the unit includes:
MOSFET technology with gold-plated RCA jacks and heavy-duty aluminum heat sinks. Essential Setup Tips