IFC’s newest comedy “Portlandia” — created by and starring Carrie Brownstein and Fred Armisen — is cranking up the indie rock appeal by guest starring three prominent musicians in their next episode. Colin Meloy, James Mercer, and Brownstein’s former Sleater-Kinney bandmate Corin Tucker are set to appear as the fictional band “Echo Echo” in the fifth episode entitled “Blunderbuss,” scheduled to air February 18th at 10:30 p.m.