Which system component is not physically connected to the Mainframe?

The TC Icon is a component that is designed to function wirelessly or via a network connection, enabling control of the System 6000 without requiring a physical connection to the Mainframe. This design choice allows for more flexibility in operation, as the TC Icon can be used from different locations within the studio environment.

In contrast, other components such as the ADA 24/96 card, DSP AES, and Remote CPU all involve direct physical connections to the Mainframe. These connections are necessary for facilitating data transfer and communication between these components for signal processing and routing within the System 6000 setup. The ADA card, for example, connects to the audio inputs and outputs, while the DSP AES handles the digital signal processing, both requiring secure connections to ensure optimal performance of the system. The Remote CPU, while it may be situated away from the Mainframe, still relies on a physical link for operation.