The PSI Audio AVAA C20 is an excellent solution for combating room modes at frequencies below 100Hz. Thanks to its active electronics and its innovative acoustic concept, it offers producers a more accurate, analytical sound image by reducing the reverberation time of low frequencies – with an effect comparable to that of a passive bass absorber 25 times its size. Importantly, the AVAA C20 doesn't generate counter-sound (anti-noise) in the room; neither does it need any fine-grade calibrating or necessitate costly structural modifications to the space itself. This makes the AVAA C20 much more flexible than conventional bass absorption solutions, allowing it to be integrated into existing setups far more easily.
The PSI Audio AVAA C20 is an Active Velocity Absorber, to give it its full name. What this means, put simply, is that it converts the maximum sound pressure that builds up at boundary surfaces into particle velocity using an acoustic resistance – a finely perforated metal plate. An integrated microphone at the boundary measures this velocity data and sends it to the active electronics: A loudspeaker located behind the acoustic resistance then compensates for the particle velocity by emitting sound waves in opposite phase into a heavily damped acoustic chamber. Despite having a surface area of just 0.2m², the AVAA C20 achieves an equivalent absorption area of 0.6 to 4m², depending on the source's frequency and the device's position in the room.
Developed in collaboration with two Swiss universities, the PSI Audio AVAA C20 improves acoustics in professional settings like recording studios and broadcast vans, but also residential and commercial spaces. It delivers a noticeable improvement in sound quality by reducing room modes, which cause frequency build-ups at walls and standing waves within the room, leading to an undefined and imbalanced sound image. Thanks to its compact size and broadband characteristics, the AVAA C20 is also significantly more flexible, cost-effective, and space-saving than conventional passive absorbers, which must be precisely tuned to specific problematic frequency ranges to be effective.
PSI Audio, a brand under Relec SA, is based in Yverdon-les-Bains, Switzerland. The company was originally founded in 1977 by Alain Roux as Roux Electroacoustique, specialising in Hi-Fi speaker development. In 1988, the company was restructured as Relec SA, expanding into PA and studio markets while producing both proprietary models and OEM products for renowned brands like Studer (1992–2003). The PSI Audio brand launched in 2004, offering premium studio monitors for professional users. These products are known for their fully analogue circuit designs and meticulous Swiss craftsmanship, ensuring exceptional performance and reliability for audio professionals.
For the PSI Audio AVAA C20 to function at its best, its placement within the room is critical. Ideally, this active bass absorber should be positioned up against a wall – or even better, in a corner of the room. Still, it's important to ensure adequate air circulation behind the unit to prevent the integrated electronics from overheating. The AVAA C20 is effective at reducing room modes between 15 and 150Hz within a radius of 1 to 1.5m around its placement: For this reason, anyone setting up their recording space should avoid placing large reflective objects in its immediate vicinity, as they can reduce its effectiveness. Ideally, the walls near the unit should be smooth and uninterrupted.