If you’ve ever converted a film or NTSC video to PAL format and noticed the audio suddenly sounded slightly higher in pitch—like everyone was speaking just a bit faster or the music was a semitone sharp—you weren’t imagining things. This is one of those technical quirks that has plagued video professionals for decades, and it all comes down to a seemingly small frequency difference of 458.2 Hz that creates a pitch shift of approximately 70 to 71 cents. I remember the first time I encountered this problem. I was working on a documentary project that required converting some archival NTSC…