In 2002, Hahto went to New York to study jazz drumming. Hahto was a member of the grindcore band
Rotten Sound. In 2004 Hahto became one of the founders of the band
Wintersun and Hahto performed on all live shows since that date. On 15 July 2019, Hahto became Nightwish's permanent drummer following Nevalainen's decision not to return to the band. In December 2020, it was announced that Hahto would be the drummer for the new lineup in Finnish black metal band
Darkwoods My Betrothed, who had become active again. ==Discography==