A loudspeaker enclosure including: - a box at least partially spherical and including a spherical zone, - a plurality of loudspeakers (30A, 30B) having convex mobile membranes (32A, 32B), the convex side being turned toward the outside of the enclosure, the loudspeakers (30A, 30B) being substantially identical and installed in a wall of the box, and - the box surrounding each mobile membrane (32A, 32B) and including an outer surface bounded by an inner edge (Γ') situated facing each mobile membrane (32A, 32B), each mobile membrane (32A, 32B) including a peripheral edge (Γ) situated opposite the inner edge (Γ) of the box and forming a closed loop, - over a continuous portion (Γ") of the peripheral edge (Γ) representing at least 25%, preferably at least 50%, still more preferably at least 90%, of the length of the peripheral edge (Γ), for any first point of the continuous portion (Γ") and any second point (M') situated on the inner edge (Γ') at a location such that the distance between the first point and the second point (M') is minimal, each membrane (32A, 32B) has, at the first point, a first tangent plane (P M), and the outer surface of the box has, at the second point (M'), a second tangent plane (P' M), the first tangent plane (P M) and the second tangent plane (P' M) being substantially coincident with one another, - the mobile membranes (32A, 32B) are in the form of a solid spherical cap with the same curvature as the curvature of the spherical zone of the box, the mobile membranes (32A, 32B) substantially extending the spherical zone of the box to form, in the idle position of the mobile membranes (32A, 32B), a substantially continuous spherical surface, and - the loudspeakers (30A, 30B) have stationary parts (42A, 42B) secured together rigidly, the loudspeakers (30A, 30B) being distributed angularly around a distribution axis (Z-Z) so as to successively form angles (γ) between them substantially equal to 360° divided by N, N being the number of loudspeakers (30A, 30B). - a box at least partially spherical and including a spherical zone, - a plurality of loudspeakers (30A, 30B) having convex mobile membranes (32A, 32B), the convex side being turned toward the outside of the enclosure, the loudspeakers (30A, 30B) being substantially identical and installed in a wall of the box, and - the box surrounding each mobile membrane (32A, 32B) and including an outer surface bounded by an inner edge (Γ') situated facing each mobile membrane (32A, 32B), each mobile membrane (32A, 32B) including a peripheral edge (Γ) situated opposite the inner edge (Γ) of the box and forming a closed loop, - over a continuous portion (Γ") of the peripheral edge (Γ) representing at least 25%, preferably at least 50%, still more preferably at least 90%, of the length of the peripheral edge (Γ), for any first point of the continuous portion (Γ") and any second point (M') situated on the inner edge (Γ') at a location such that the distance between the first point and the second point (M') is minimal, each membrane (32A, 32B) has, at the first point, a first tangent plane (P M), and the outer surface of the box has, at the second point (M'), a second tangent plane (P' M), the first tangent plane (P M) and the second tangent plane (P' M) being substantially coincident with one another, - the mobile membranes (32A, 32B) are in the form of a solid spherical cap with the same curvature as the curvature of the spherical zone of the box, the mobile membranes (32A, 32B) substantially extending the spherical zone of the box to form, in the idle position of the mobile membranes (32A, 32B), a substantially continuous spherical surface, and - the loudspeakers (30A, 30B) have stationary parts (42A, 42B) secured together rigidly, the loudspeakers (30A, 30B) being distributed angularly around a distribution axis (Z-Z) so as to successively form angles (γ) between them substantially equal to 360° divided by N, N being the number of loudspeakers (30A, 30B).