Rock's replacement singers are too often overlooked. Some bands actually soar to their greatest heights long after an original frontman has departed. More often, however, these successor stars become saddled with towering expectations as groups attempt to resurrect past glories when a famous guy leaves.

The following list takes in the full range of these lineup changes – some sparked by internal struggles, others by sudden deaths. Certain small revelations happen along the way.

For instance, there remains a large, very vocal contingency of fans that define Journey by their Steve Perry era. But he actually wasn't their first lead singer – or even their second. And Journey are not alone. Bands that have had three or more frontmen include AC/DC, Black Sabbath, Deep Purple, Anthrax, King Crimson, Van Halen and Yes, among many others.

Groups often begin with embryonic talents at the mic, school chums or neighborhood friends who ultimately go by the wayside as fame's spotlight brightens. Unfortunately, tragedy also sometimes sparks these switches at the mic: Bands like Queen, Stone Temple Pilots and Lynyrd Skynyrd somehow found a way to soldier on.

Luckily, happy reunions aren't uncommon: Acts like Iron Maiden, Deep Purple, Van Halen, Bad Company and Black Sabbath have seen various singers come, go and then come back again.

The following list isn't a comprehensive history of frontmen and their various eras; instead, we've focused on the most notable of changes up front. Keep scrolling for a look at rock's replacement singers.

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