Abbreviation for audio frequency, a range that extends from 10 Hz to 20 kHz.
"I received my recordings in the mail yesterday. To say I am pleased with the end result would be an understatement. The original recording has been in it's original paper sleeve and stuffed into a trunk for years. As it's a 78rpm recording and I have no player for that speed recording, I could not listen to it beforehand. When I received the ..."