This Studer card (Part Number: A949.0427) offers four analog microphone/line inputs, a great addition to your D21m system.

To use this Studer card, simply install it into your D21m Modular I/O System. Connect your microphones or line - level audio sources to the four analog inputs. When you're done, turn off the system properly. Keep the card in a clean and dry place. Avoid exposing it to extreme temperatures or humidity. Regularly check the connections to make sure they are secure. If you notice any issues, contact Studer support.