(NEXSTAR) – Casual fans will be watching the theatrics, choreography and guest appearances during Kendrick Lamar and SZA's Super Bowl halftime show. Sleuths will be watching their throats.

It's one way to tell if a performer is relying on a backing vocal track, or lip syncing. Some performers choose to lip sync to ensure a good show, especially during high-action high-pressure situations.

Sometimes lip syncing is plainly obvious, like when you can tell the singer's mouth isn't moving in time with the lyrics. But sometimes it's more subtle.

One thing you can look for is the positioning of the performer's microphone. If it moves closer and further away from their face, but their voice remains constant, they're probably lip syncing to a track. With live vocals, you'd expect the singer's voice to sound quieter or louder depending on the position of the microphone.

A singer’s vocal........

© The Hill