Hard-rockin' radio station to broadcast from London tube, using public Wi-Fi

Mind the gap -- the gap between songs, that is. A hard-rockin' UK radio station plans to do Friday's breakfast show from deep in the bowels of the London Underground, using the public Wi-Fi available to commuters. It's both an interesting technical experiment and a rolling chance to rock out.

The show will be broadcast on TeamRock Radio, the headbanging channel connected to none-more-black magazines Metal Hammer and Classic Rock. Breakfast show DJs Moose & JRock will attempt to beam all their links live from various stations to demonstrate the power of Wi-Fi.

Popularly known as the tube, London's underground train network -- at 150 years old, the oldest in the world -- has enjoyed Wi-Fi on platforms and in stations since 2012. Virgin Media connected the infrastructure, and you can gain access through your phone network.

Starting at 7 a.m. GMT -- on Friday the 13th no less -- the intrepid radio adventurers will journey from Southwark station, just south of the Thames, travelling on three tube lines and broadcasting from 10 stations before celebrating success with a well-deserved McDonald's breakfast in Stratford in East London.

To find out more about the plan, I caught up with Moose, head of radio at TeamRock and co-host of the show.

The idea isn't just a fun stunt: it's a proof of concept for a radio station without borders. The idea was born of a "combination of the knowledge there is a codec in Chrome and a burning desire to rid ourselves of fixed broadcast sites," says Moose. "TeamRock.com has a global view and we want to broadcast when and where we want. Chrome and a bit of kit eliminate virtually all the logistical challenges, lead times, and costs of ISDN and satellite options."

Moose admits, "We know there are many variables out of our control." But a recce proved successful: "We carried out a trial run earlier today to identify locations to do links from. All was successful using two different Wi-Fi providers.

"The broadcast will test the quality of the Wi-Fi freely available on London Underground and in McDonalds during a peak period, so it will be a true test of how well these networks cater [to] the public. The aim is to show how usable Wi-Fi networks are, with any shortcomings being exposed as we go."

The cramped conditions of the tube at rush hour mean the boys have to stay light on their feet. "The technical solution is focused on the least amount of equipment required to provide an acceptable quality link to the studio using any reasonable quality Wi-Fi connection. To keep things compact, a MacBook Air and Pro USB Audio interface unit will be used with two Shure SM58 microphones and two pairs of Beyer headphones for the presenters. All of this equipment will be housed in a simple backpack making it very portable and easy to set up," Moose said.

"The link back to the studio uses software which is based around use of the built in Audio Codecs in Google Chrome. This software makes establishing the broadcast link very simple via a browser log-in. Visual talkback via a chat box is also part of the software programme, allowing prompts and updates to be sent easily from the studio.

"The main technical challenge is finding Wi-Fi networks which have robust wireless coverage coupled with good-quality Internet connectivity. Broadcast audio is transferred in real time, with minimal buffering (<10ms), so high quality connectivity with very little packet loss is required to enable a stable high-quality link. The data rates required for such a link are < 200Kbps using modern audio compression built into the Chrome Browser codecs. Given most Wi-Fi networks provide 2Mbps or above as a minimum speed, transfer of 200Kbps should be achievable -- assuming the Wi-Fi isn't over-subscribed."

He continued, "Two sets of technical kit will be available in case of one failing." And if things do go wrong? "The backup plan is to play 'In-A-Gadda-Da-Vida' by Iron Butterfly, which is a 17-minute-long song, to allow us to find a good connection."

You can stream the show online at teamrock.com or listen on a DAB radio in the UK. If 7 a.m. is a bit early for you (that's 6 p.m. Friday in Sydney or 11 p.m. Thursday in San Francisco), the team's underground adventure will be available online on demand for 30 days at Team Rock's catch-up service. Fingers crossed we won't be hearing that distinctive gothic organ and bass line...