Yes, a digital cable box functions in effect just like a stand-alone component tuner . . . conceptually very similar to an audio tuner. It provides all the on-screen program guides and channel selection.
As far as the audio goes . . . all of the industrial monitors have basic audio source-switching and preamp functions, as well as a little (i.e. 7 watt) stereo power amp to run some optional accessory speakers that can bolt on the side. But for a system where you want high quality audio . . . the audio sections of ANY mass-market television or monitor should be avoided, as they're typically very noisy. So usually, some sort of receiver or processor (the audio/video correlary to an audiophile line preamp) is used for audio decoding and preamp functions, and for video source switching . . . the latter of which is passed to the monitor for viewing.
As far as the audio goes . . . all of the industrial monitors have basic audio source-switching and preamp functions, as well as a little (i.e. 7 watt) stereo power amp to run some optional accessory speakers that can bolt on the side. But for a system where you want high quality audio . . . the audio sections of ANY mass-market television or monitor should be avoided, as they're typically very noisy. So usually, some sort of receiver or processor (the audio/video correlary to an audiophile line preamp) is used for audio decoding and preamp functions, and for video source switching . . . the latter of which is passed to the monitor for viewing.