How to bridge amp channels on the CM-series 70 Volt amplifiers

How to bridge amp channels on the CM-series 70 Volt amplifiers

The CM2-750, CM3-750, and CM4-750 all have channels that can be bridged together to deliver more power to your speakers. If you need to provide power to 100V speakers, you need to use bridging to ensure you get enough power to your speakers.

On the CM2-750 and CM3-750, use the Positive (+) Channel 1 terminal and the Positive (+)  Channel 2 terminals for bridging:




Warning
On the CM3-750, channel 3 cannot be used as a bridged output.

On the CM4-750, the positive terminals for channels 1&2 can be bridged together, and positive terminals channels 3 & 4 can be bridged together:

Warning
Make sure the A/B dip switches are in the correct position for your install. If you are bridging to 70v speakers or an 8 Ohm speaker, make sure the switch is UP in the A position. If you are running to 100V speakers, make sure the switch is DOWN in the B position.



Bridged outputs have a minimum impedance of 8 ohms. DO NOT connect a 4 ohm speaker to a bridged channel.


In the web interface for the CM amplifier, open the global settings (Gear Icon in top right corner), and open the Amplifier settings panel. Under the "Bridge" option, click the check mark box next to the outputs you're using in bridged mode. This will combine the 2 output zones together to ensure both channel always output the same audio and are powered equally.



Warning
If this box is not selected, no audio will output to your bridged zones