Method and apparatus for providing volume control with DC supervision

A volume control, comprising:

• a first input interface for receiving an audio signal in an alternating current (AC) signal;
• a first output interface for forwarding said audio signal to at least one audio device;
• a second input interface for receiving an alarm signal in a direct current (DC) signal, wherein the alarm signal provides supervision of a notification appliance circuit;
• a switch having a plurality of nodes, wherein at least one of said plurality of nodes is an unlabeled node, wherein said switch is in communication with said first input interface and said first output interface for controlling a volume of said audio signal that is sent to said at least one audio device;
• and
• a first filter that is coupled to said unlabeled node of said switch.

A volume control, comprising:

• a first input interface for receiving an audio signal in an alternating current (AC) signal;
• a first output interface for forwarding said audio signal to at least one audio device;
• a second input interface for receiving an alarm signal in a direct current (DC) signal, wherein the alarm signal provides supervision of a notification appliance circuit;
• a switch having a plurality of nodes, wherein at least one of said plurality of nodes is a common node, wherein said switch is in communication with said first input interface and said first output interface for controlling a volume of said audio signal that is sent to said at least one audio device;
• and
• a first filter that is coupled to said common node of said switch.