If our city fathers really want us to take to Eastside, then somehow they must change our perception of it as the armpit of Birmingham. It's difficult to get to, parking looks like a nightmare (I chickened out and went by taxi), and it seems devoid of human souls as well as soul-less itself.

But what happened there on Sunday afternoon was nothing short of amazing, when Birmingham Contemporary Music Group hosted the world premiere of David Lang's Crowd Out, a vocal piece employing no fewer than 1000 community performers and 20 conductors, marshalled by various coloured flags and megaphones.

The idea is actually quite dated, as we were doing this kind of thing in the 1960s. Scribble down a few vox pop quotes, shuffle them into some kind of order, and let your performers stand and deliver. Hand gestures will help the visual engagement, and perform as though you believe in it.

But what was different from the olden days was the sheer commitment and expertise of these amateurs drawn from all over the Midlands, and who had been brilliantly prepared and rehearsed top-down from the directorship of Simon Halsey, no less. And there was a real structure to this piece, its theme of loneliness among crowds bringing to mind Holst's Hymn of Jesus, and its central point a moving melodic confession.

The atrium of Millennium Point proved a perfect performing venue, with a natural acoustic accommodating the variously-arranged choral groups, and comfortable space for the i-pad camera-toting punters. The piece will be repeated in Berlin and London, and Simon Halsey was jetting off immediately after these two Birmingham performances (there was a repeat an hour later) ready for a rehearsal in a Berlin carpark early the next morning.

"Where Birmingham leads," he told me, "Berlin and London follow."