The Audio Hotspot first takes analog audio feeds and converts them to digital audio signals.  The digital audio signals are sent to a processor, which converts them to bitstreams and assigns each bitstream a unique channel number.  The channelized bitstreams are sent to the hotspot network, where wi-fi access point(s) broadcast them to portable devices. 
Each portable device uses a downloaded App to tune to the channel for the audio they wish to hear.  In this diagram, channels 1-4 contain the audio for television displays 1-4.  In a sports bar, or exercise club, the client would choose the channel for the TV, and hear the audio through their portable device speaker or earphones/headphones plugged into the headphone jack.
The Audio HotSpot requires a connection to the internet.  An Administrator Portal allows the Audio HotSpot owner/manager to create advertising and other content to be displayed on the portable devices.  The internet connection from the HotSpot system to the Administrator Portal maintains the operating software and HotSpot service. Since the HotSpot includes external internet access, the client's portable device can also use the internet while they are connected to the Audio HotSpot network.