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What was Symphony X's underworld?
Underworld is the ninth studio album by American progressive metal band Symphony X.
When was Symphony X's underworld album released?
Symphony X's Underworld was released on July 24, 2015 through Nuclear Blast.
How was Symphony X's underworld album received?
Symphony X's Underworld received 4 stars from AllMusic
When did the band Symphony X take a break?
According to singer Russell Allen, the band Symphony X entered a short hiatus during 2017 in which they did not perform.

Question: What was the reason for the break?
Self-contained rewrite: What was the reason for the band Symphony X's break?