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The Digital Face-Plant: Thoughts on IP Security
Few things matter as much in classical music broadcast engineering as audio fidelity. That's one of the reasons The Classical Network plunged forward a few years ago into the world of digital radio. Regardless of what digiphobes tell you, analog technology and analog FM cannot rival digital audio and digital radio (HD Radio) for music fidelity in at least four areas critical to musical genres like classical music: frequency response, signal-to-noise ratio, dynamic range, and eliminating musicality-killers like limiter clipping.
But, as we have learned the hard way at The Classical Network, digital paths offer the opportunity to plant your teeth firmly in the gravel. The painful experience comes with a caveat emptor: the folks who sold you the digital technology can disappear as quickly as data packets when the problems outrun the solutions.
Three years after abandoning satellite delivery for our network stations and entering the brave new world of Internet delivery to get better audio quality, we are returning to satellite audio delivery to avoid hackers and restore consistent audio. In the process, we are accepting lower quality audio in exchange for the even-more-important coin of the realm in broadcasting: reliability. We learned valuable lessons by being early adopters, but some of the mistakes could have been avoided.
Ironically, our odyssey began as our audio improved, not as we searched for better audio. As our flagship station's audio technology grew steadily better over the past decade, we noticed that our satellite audio -- stable, but 30-year-old technology -- didn't sound all that stellar in the field. The ubiquitous stringed instruments of classical music often sounded more brittle and ragged than they did in the day of tube transmitters and telco-loop studio links. Improved technology feeding the satellite uplink and following the satellite downlink made other audio problems in the chain -- including the satellite chain -- even more obvious.
About the same time these audio issues became more apparent, we launched our HD2 network of jazz stations. Faced with a need to double our satellite bandwidth (meaning higher costs for two channels of marginal audio), we started looking at our options.
One of our more-trusted equipment vendors suggested that we look at IP codecs that he assured us were popular in Europe. The codecs promised audio that was nearly indistinguishable from uncompressed digital audio, even when delivered over public Internet.
When we heard the codecs, they did sound impressive. Some of our hosts with highly trained ears could hear subtle differences between the original uncompressed audio and the codec algorithms, but the codecs were vastly superior to the audio we were getting from our satellite system. Better still, with some careful failover configurations coupling low-cost bandwidth from two or three business-class Internet providers, we calculated that we could run both our classical and jazz networks over public Internet for less than we were paying for just mediocre classical music delivery by satellite.
After we launched, the system garnered us some trade publication ink, and it worked so well that we quickly started buying the blue rack units for more locations and adding more bandwidth. We added the units to venues in New York City and Philadelphia. Eventually, we were broadcasting live concerts that provided a fully-digital experience for classical music lovers anywhere in the world in stunning quality, just a few seconds after the same music was heard by those sitting in the famed venues of New York and Philadelphia.
We succeeded in looking toward the future of classical broadcasting: we delivered fully-digital audio from NYC to our studio, then out our digital radio pathway to NYC, Philly, and New Jersey, plus to Internet listeners around the world, all within seconds of the live performance. It was all kept in the digital domain, in stunning quality.
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