Diffusers
Diffusers: For vibrant sound instead of bare walls
While absorbers selectively remove energy from the room, diffusers pursue a different mission: they increase the diffusivity of the sound field. The result is a vibrant, natural sound image in which sound reflections are evenly distributed throughout the room instead of bouncing back sharply and directionally.
From Baroque rosettes to modern acoustics:
In historical concert halls, rich decorations and figures served as natural diffusers. These structures are often lacking in today's often minimalist architecture, making the targeted use of special diffusers essential in studios and practice rooms.
How scattering works: Two ways to achieve diffusion
An effective diffuser deflects sound energy away from the direction of geometric reflection and distributes it over a wide angular range. This is achieved physically in two ways:
1. Spatial structures
Geometric shapes such as half-cylinders or prisms scatter sound mechanically. The structures must be on the order of the wavelength to be scattered.
2. Location-dependent wall impedance
Scattering occurs due to varying acoustic surface properties. The juxtaposition of different materials alters the relationship between sound pressure and particle velocity (wall impedance).
Mathematical precision: Schroeder diffusers
Sophisticated systems such as maximum sequence diffusers (MLS) or quadratic residue diffusers (QRD) use mathematical sequences of numbers for perfect scattering:
- These so-called Schroeder diffusers consist of depressions with mathematically defined, different depths.
- The varying depths cause a phase shift in the reflected sound waves, which guarantees excellent and uniform scattering.
Evolution: Microperforated Diffusers
An innovative further development is microperforated diffusers . Here, sound-reflective strips are replaced by microperforated resonators.
Advantages of the combination (e.g. with HSA3):
- Hybrid effect: Simultaneous scattering in the mid and high frequency range with targeted absorption of critical frequencies.
- Slim design: Micro-perforation allows for a significantly shallower installation depth compared to solid, classic diffusers.
- Sonic balance: Prevents flutter echoes and booming resonances without "overdamping" the natural liveliness of the room.
Micro-perforated diffusers create an acoustic environment that sounds equally controlled, clear, warm, and vibrant.