With the proliferation of smart phones, radio communication has become incredibly difficult to make reliable in stadium settings. To address this for Ariana Grande’s Honeymoon tour, Brian Mayton and I, along with Bill and Nick at Shure, designed custom hardware and software to support wireless control of Ableton and hardware vocal effects using the UHF and 2.4Ghz band. Here is a short excerpt from the documentation for the project that explains some of the challenges:
Radio is not trivial to understand and utilize– often it is considered to be one of the most complex elements of live production. This is partly because it is hard to conceptualize the behavior of radio. There are many standards which governing bodies such as the FCC, or their equivalent around the world, use to keep the airwaves organized so that it’s possible for many many devices co-exist. It is our job to adhere to these standards while ensuring the required functionality and reliability of the radio equipment.
A good analogy for radio is voice. Imagine James Earl Jones reciting Hamlet quietly in a room along with 20,000 young children playing loudly. Regardless of the fact that toddlers have much higher pitched voices than Mr. Jones, they still contribute to a general din that makes it hard to understand the text being recited.
In our case, the toddlers are iPhones and other mobile devices in the audience. Each device sends out a packet, a message, into the airspace. It is up to us to choose equipment which helps our message to be sent as ‘loudly’ as possible and received clearly. Often times this means choosing directional equipment which favors messages coming from a certain location, such as the stage. When radio systems perform poorly in a performance context, it is because there are too many devices trying to send and receive messages. If our ‘voice’ cannot be louder than 20,000 others combined, it becomes hard to hear that or any message; this often results in a complete blackout of all radio communications. No device can ‘hear’ any others because the background noise is so great.