If you jumped on the DAB+ digital radio bandwagon when the service officially launched earlier this month, you may have noticed that there's about a five second delay between it and the old analogue transmission. Jez Ford over at AVHub managed to find out exactly what causes the delay, and it's quite interesting...
After contacting Joan Warner, CEO of Commercial Radio Australia, Jez got this response:
"There are a number of separate causes of delay in the DAB+ digital radio chain from the studio to the multiplexer site.
"Audio encoding delay – 0.3 seconds. (this is the delay for the encoder to turn audio into DAB+ audio. Service Multiplexer Buffering delay – 0.4 seconds Service Multiplexer error protection delay – 0.2 seconds Ensemble Multiplexer Buffering delay – 0.8 seconds Ensemble Multiplexer error protection delay – 0.8 seconds Transmission interleaving delay – 0.768 seconds
I think it's fascinating that they can pinpoint the length of the delay to 1/1000th of a second in regards to the transmission interleaving delay. That's just nuts.
Head over to AVHub to check out the full response, as well as a fuller rundown on digital radio's early setbacks.