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Worldcast Systems - Radio & TV Broadcast Solutions



APT IP Codec - not quite teleportation but close!

  3 oct. 2016

When a show co-host relocates 200 miles away, how can you make it seem like he is in the same room? 
Dave Supplee, Regional Engineering Coordinator, Northeastern U.S. Cumulus Media...

WICC(AM) has been a fixture in Southern Connecticut for generations. Recently long-time News Director and morning show co-host Mike Bellamy needed to relocate to Central Pennsylvania due to family commitments. We needed to find an engineering solution that would enable him to continue his role on the station and stay on the show.

We needed somehow to ensure that, while working out of the Cumulus studio in Harrisburg, Pa., Mike was able to seamlessly interact with fellow host Tony Reno back in Bridgeport, Ct. Low latency and a high degree of reliability would be critical in order for the audience not to notice that the hosts were actually over 200 miles apart.

In the past, the only viable solutions to achieve this would have been an ISDN line or dedicated telco T1 link which are both expensive options. We discovered an alternative in APT’s  IP codec with SureStream technology.

For us, this delivers a more economical alternative as the APT codec simply utilizes the existing house Internet links so we didn’t need to install or pay for any new lines. On the Harrisburg side we have both a 20 Mbps Internet connection from Frontier and a Comcast cable modem. We have a similar arrangement in Bridgeport using our dedicated business Internet service and a second, less expensive connection, primarily used for backup purposes.

Having looked at a few other codecs from different manufacturers, we felt that the APT box offered the best combination of low latency and robustness and at an affordable price. It also helped that we have had positive results at other Cumulus markets throughout the country with APT codecs. One example is for network origination from our Nashville studios to the Westwood One Networks satellite distribution facility in New York.  

In order to get the full benefit of APT’s SureStream data signal redundancy technology, we connect the APT codecs at each studio to both the primary dedicated Internet and secondary Internet links, which protects the content against any dropouts and outages. When we first installed the units back in the fall of 2013, all went well but we did notice some occasional dropouts on the line that concerned us. A quick investigation uncovered that one of the codecs was only connected to a single link and so we weren’t actually using SureStream to its full potential. Since we fixed this issue, the system has worked flawlessly without a single dropout in the last six months.

To achieve the low-latency connection that we need, we use the Enhanced aptX algorithm on the APT codec which keeps delay to a minimum and keeps the audio quality at a high level. With SureStream, we can also keep the latency consistent throughout the broadcast so that the hosts do not have to deal with any drift which could cause them unnecessary distraction. Some of the AoIP codecs that I reviewed offer methods to deal with the constantly changing behaviour and latency of Internet but many involved scaling back the audio quality and/or altering the latency in order to keep the link alive. For a live, interactive broadcast, this just doesn’t work for us so consistently low latency was a critical factor.

The APT codecs and SureStream have enabled us to continue to deliver “Tony & Mike in the Morning” on WICC without the audience noticing that anything has changed. Perhaps the greatest testament to just how well it works is the fact that members of the public often drop by the Bridgeport studio to see the hosts. We just tell them that Mike is in the bathroom!