I listen to a number of radio programs that have a “delay” in place to block out anything that is not suitible to go out over the airwaves. There is usually a “dump” button that someone presses to “dump” the offensive word(s). Often, if the dump button gets used too often is succession, they have to “bulid up the delay” before it can be used again.
I am usually very good at internet searches but I’m running out of patience trying to find an explanation of how this process works. I have always been curious. Can anyone shed some light?
It’s simple enough. You have a tape recorder. Usually, they are designed to have both the record and play heads in the same spot. For a tape delay, you have a record head in one spot, and the play head apart from it – so far that it takes seven seconds for the tape to reach it.
The signal is recorded onto the tape, which takes seven seconds to reach the play head. The play head picks it up and broadcasts it. If something inappropriate is said, you turn off the play head and the word doesn’t get out.
Nowadays, it’s probably done electronically, but the principle is the same.
baileygrrr
Been listening to Don and Mike?
The modern way of doing this is with a digital delay system. First the audio signal is digitized, then put into memory for storage. At first, as the data comes in it goes out the other side, but slowly the delay system begins building up a delay. As long as it builds up slowly, the distortion in the audio signal caused by adding the delay isn’t noticable by your ears. Eventually the system works its way up until it is storing about 15 seconds of audio between its input and output. If someone says a naughty word, the operator has a certain amount of time where they can hit the “dump” button, and not only does the bad word not come out, but you also don’t get several seconds of dead air like you would in the old tape delay systems that RealityChuck described. But now you’ve lost your delay and have to slowly build it back up again, so if someone says another bad word, this time (before the delay builds back up) there would be dead air.
Radio is very picky about avoiding dead air, because they are afraid if their listeners hear silence for too long they’ll switch to some other program. It’s kind of odd when they hit the dump button though becuase it kinda sounds like your CD skipped. The sound just instantly jumps ahead 15 seconds.
Television, especially some movie channels, will also make use of digital techniques to speed up or slow down movies to make them fit in a particular time format. As long as they don’t speed it up or slow it down too much your eyes and ears can’t tell they are doing it.