Entering the voluminous hall via a narrow passage is a carefully composed moment of compression and release. Ahead, a splendid view of the gardens reappears through double-height windows fitted with 21-foot-high pivot shutters that close at the touch of a finger. “In performance spaces, glass is not the designer’s friend,” says project director Guy Hollaway. “With this arrangement, audience members can reorient themselves before taking their seats, then the shutters close to create perfect acoustic conditions.”

Establishing what those should be was not straightforward. The hall, which hosts open-to-the-public touring performances, not only has to work for a full orchestra and rock bands, but also accommodate all manner of everyday school activities and allow the principal to address the whole student body without amplification. From the initial stages of the design the architects worked closely with acoustician Matthew Harrison of Buro Happold to refine every architectural detail. “We sat in their auralization room and used advanced software and our 3D model to tune the entire building,” says project architect Aaron Bright. “That allowed us to ensure that every audience member hears the same thing.”

The dimensions and shallow camber of a timber diagrid roof were developed to diffuse sound in a way that makes the room feel larger and more resonant without creating echoes. Within the elliptical double-height volume, balconies define a rectangular space on the first floor, whose more intimate scale is intended to give reassurance to young performers. Their flat fronts produce early reflections that allow musicians to hear themselves while the curved walls of the upper level amplify sound for the audience, giving a cathedral-like reverberation time of four seconds.

Large areas of the walls are lined in planks of solid maple routed with grooves of varying width and depth that were calculated to control flutter echoes caused by sound bouncing between hard surfaces. “It’s beautiful too,” says Hollaway. The pale wood blends harmoniously with birch-faced plywood paneling, oak floors, and the composite glulam beams of spruce and poplar to make an interior whose visual warmth matches its auditory qualities. A slight similarity to the view through the sound hold of an acoustic guitar is inadvertent, says Hollaway.

Acoustic considerations also directed the specification of a concrete frame infilled with walls of concrete blocks, which provides the best defense against unwanted vibrations, and even influenced the building’s outward appearance. The super-sized ducts required by a soundless low-speed, high-volume ventilation system are installed on the outside of the hall, largely veiled by the inclined facade of black perforated metal and close-space fins of gold anodized aluminum. Here, the resemblance to an instrument is intentional: Hollaway Studio had in mind harp strings or the soundboard of a piano. The lustrous metalwork also blends well with the colors of nearby trees throughout the changing seasons.

A quieter counterpoint is made by the adjoining Music School, which provides more than 20 teaching and practice rooms along with recording facilities and a 120-seat recital hall. Architectural details of nearby buildings are reinterpreted in pale brickwork and deep-set windows framed in crisp chamfered stone. Inside, the faceted facade produces little niches in each of the sound-proof teaching rooms, which are used either for purpose-made instrument storage or as bench seats intended to offer a respite from the pressures of formal study.

In the larger rooms and the recital hall, acoustic conditions have been matched—with some difficulty—to those of the concert hall itself, helping to prepare students for the experience of the big stage. “That’s one of several ways in which we’ve tried to build the confidence of the girls on their musical journey through the school,” says Bright.

There is an appropriate sense of ceremony about the culmination of this journey, as performers prepare in a wood-paneled robing room before crossing the bridge to the hall, passing through a narrow passage at one end of the ellipse and arriving on the second-floor balcony of a room—or an instrument—that they have already learned to play.

The experience enjoyed by the school’s fortunate pupils is also shared with the wider community, as the hall hosts summer camps for local young musicians, and concerts by professional orchestras. The inaugural concert was given by the London Philharmonic. It was, says Hollaway, a “joyous” occasion and no doubt the first of many to come.