There’s a higher percentage of excellent singers in Dirty Projectors alone than you would probably find in a sampling of hundreds of different  Indie bands. Four of the six members are talented enough to front their own band, but to split them up and share them equally throughout the Indie scene would be a travesty. As a unit they create a near overwhelming harmonic crescendo, their voices exploding with vivacity, filling and colouring the room with dazzling flashes.

They waste a little time demonstrating their band defining ability as they stroll onto the Roundhouse stage. David Longstreth, primary songwriter and general leader, taking his place in front of his inconceivably tall microphone stand that it turns out was not extended so high because of a roadies error. They begin as a four piece with a run through of new album title track “Swing Lo Magellan”, just as you wonder that maybe they only tour with four members and begin to mourn the loss of harmony you notice the unmanned keyboards, and sure enough the end of the song sees the entrance of Olga Bell and Haley Dekle. Joining Longstreth and Amber Coffman and unleashing the full force of the band.

Perhaps the most outstanding vocal moment comes when Longstreth steps back and joins the rhythm section, as the three women sing “Beautiful Mother” from their 2010 collaborative album with Björk: Mount Wittenburg Orca. The three voices singing the hook in unison, and clapping a rhythm that the crowd never quite gets, before breaking into a startling and heavenly siren choir that garners a loud and enthusiastic response every time it’s repeated. A song dedication by Longstreth to Sam Carter is met with silence, showing that few in the audience saw Later… with Jools Holland this week, until it becomes clear that the song in question is “Gun has no Trigger”.

The rest of the set comprises entirely of songs from Swing Lo Magellan and Bitte Orca. Coffman and Longstreth trade in their vocals to instead harmonise with their guitars on the solo of “No Intention”, and a surprisingly heavy and distortion led version of “Useful Chamber” closes the pre-encore set, with the ending freakout intact and arguably a little bit space rock than the album version. Their sort-of-hit “Stillness is the Move” has the best response of the night, seeing Coffman nail a showy note briefly making the live audience audibly indiscernible from an X-Factor crowd as it’s met with a loud ovation. Short and sweet new album cut “Impregnable Question” takes them home after a similarly short and sweet hour and a quarter set. Longstreth’s painstakingly assembled harmonies sound great on record, but when you are present as those four voices come together and ascend and explode it really is something special.