When Jason Newsted was still Metallica 's bassist, he tried to get his Echobrain side project off the ground, but it was reportedly frowned upon by frontman James Hetfield .
There appears to be more freedom these days within the Metallica camp to pursue outside interests, as current bassist Robert Trujillo will be reviving his band Mass Mental? later this summer for two concerts.
Tickets for the first Mass Mental? show, taking place August 26 at the Whisky a Go Go in West Hollywood, California, are on sale now through TicketWeb.com.
The other concert is set for September 6 in Markneukirchen, Germany, as part of Warwick Open Day 2014 .
Mass Mental? began as a Trujillo side project in the late 1990s, when he was still a member of Suicidal Tendencies . He became Metallica's bassist after Newsted departed in 2001.
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