St. Luke's, Old Street - within convenient walking distance of the LSO's Barbican home - had been derelict for 43 years, roofless and blackened after subsidence had left it dangerously unstable. Yet this was a church by a crack early 18th century architectural team, Hawksmoor with John James, both heavily involved in implementing Queen Anne's "50 New Churches Act" of 1711. The hand of Hawksmoor can be seen in the extraordinary spire, which takes the form of a solid obelisk - originally plain but later fluted.

After years of successive abandoned plans to save and convert the church, things finally came good when the LSO went looking for a home for its highly regarded education and community programme, known as LSO Discovery. The orchestra's work with schools in particular is exemplary. But the church, to justify the £18m cost of rebuilding, had to become many things. It is now also a rehearsal centre for the full orchestra, an ideal live-recording studio, and a public performance space for small concerts, seating 350.

Architect Axel Burrough of Levitt Bernstein (also responsible for other enlightened conversions including Manchester's Royal Exchange Theatre and Birmingham's Ikon Gallery) has dropped a new building into the ruined shell of the old. Working with structural engineers Arup, Burrough devised a system of elegant steel branching columns to hold the massive weight of the new roof. Traditionally slated on the outside and timber-lined on the inside, the roof is in fact of super-dense concrete to prevent any noise getting out or in. Similarly, the original restored windows now have an extra internal layer of two-inch thick glass. The church is next to a busy road and under the flight path into Heathrow, but not a rumble will be heard.