Threat Signal was formed in the late summer of 2003 by cousins Jon and Rich Howard, who then added the guitarist Kyle McKnight. The trio then found drummer Adam Matthews in early 2004. Threat Signal posted their song "Rational Eyes" on an international metal chart on GarageBand.com. After a few weeks, the song reached #1, and it has received many awards including best guitars, best drums, best male vocals, best production, song of the week, and song of the day. In August 2004, Eric Papky, Kyle's former guitar teacher, joined the band on bass. Success on GarageBand.com sparked some early record label interest and helped create a following even before the band had ever played live. In August 2005 Marco Bresette replaced Eric Papky on bass guitarIn March 2007, Threat Signal began demoing new material, but was hampered by another departure, this time Marco Bressette's. The band announced a search for a new guitarist the same day. Threat Signal was tapped as the opener for the Tour and Loathing trek alongside Protest the Hero, All That Remains, Blessthefall, and The Holly Springs Disaster. Shortly after this tour, guitarist Kyle McKnight parted ways with Threat Signal in June 2007 due to personal differences with the remaining members of the band. The band's drummer, George Parfitt, also departed later in 2007 to focus on his family life. The remaining members of band, Jon Howard and Pat Kavanagh reformed the band's line-up with the new additions of drummer Norm Killeen and guitarists Travis Montgomery and Adam Weber.Threat Signal's second album Vigilance, which was produced by Howard and mixed by Greg Reely, was released on September 8, 2009 in North America and September 11, 2009 in Europe. The album spawned a music video for the track "Severed". On July 15 the band released a 32 minute "making of" video for the new record, containing footage of the recordings, song writing process and interviews with band members. The album sold around 1,100 copies in its first week of sale in the United States, with the band touring alongside Epica to support the album.