The Cab first rose to prominence at the peak of the mid-2000s emo pop trend with their debut album Whisper War (2008), which was promoted via national tours with Hey Monday and the Hush Sound.

The album boasts a wide array of songwriting collaborators, including Bruno Mars, Adam Levine and Jesse Carmichael of Maroon 5, Fall Out Boy's Pete Wentz, and production team the Messengers.

With most music and lyrics written by band members, guest artists include Pete Wentz and John Feldmann co-writing "Grow Up and Be Kids"[7] and Bruno Mars with "Endlessly."

The Cab funded the entire album, with lead vocalist Alexander DeLeon tweeting, "We paid for it all on our own and refused to take no for an answer.

"[12] Annie Zeleski of Alternative Press gave it 4/5 and said that "For loyal fans of the Cab, Symphony Soldier lives up to expectations; it's the album they've been waiting for since 2008".

[14] SputnikMusic reviewer DaveyBoy gave Symphony Soldier a 3.5/5 ("great"), concluding "At 46 minutes, the album is undoubtedly overlong and repetitive, yet there is no real filler, just some redundancy in its mid-section.