Last year 3 Days Grace parted ways with their lead singer, Adam Gontier, in a very public & bitter divorce.  The band already had a tour booked when Adam quit so when they needed to perservere they brought in a fill in vocalist.  His name was Matt Walst.  Matt is the 3DG bass player's little brother.  It was an easy call to have him join the tour as lead vocalist.  Things went well.  Matt was an obvious choice to become the "official" lead singer for the band.  That has come to fruition with the band's new single "Painkiller."  Check it out.