PSI Audio AVAA C20 defeats low-frequency noise in studios, offices and flats with its innovative technology

Yverdon-les-Bains, 23rd June 2021

Acoustically speaking, the world we live in has a problem: walls. While they do pose an obstacle against the elements and predators, they also obstruct the motion of sound waves, creating reflexions, interferences and resonances. Combating these acoustic side effects of architecture proves problematic, particularly in the low frequencies: the low end of the hearing spectrum has high energy, long decay times and requires a lot of space and material to be taken care of in traditional passive acoustics. These challenges explain why the AVAA C20 made such huge waves when PSI Audio introduced it in November 2015. And it also explains why its application has since gone way beyond professional audio environments to pretty much any place that suffers from the sonic effects of walls.

True Rumble Elimination: PSI Audio AVAA C20

The AVAA C20 was developed by PSI Audio as a compact and innovative solution for that famously hard to tackle frequency range from 15 to 150 Hz. It requires a lot less space than traditional porous absorbers dealing with the same frequencies due to its active approach. However, its clever technology works without specific resonances, DSP or anti-sound, hence acting latency- free and without calibration. It just sucks the resonant sound waves out of the room – which also means that the result is not specific to one listening spot, but the overall acoustic performance of the room is improved. The room modes simply disappear, the rumble is eliminated, leaving a sharper, more precise bass, clearer mids and crisper treble by reducing the total sonic energy in the room. With a device this efficient, it is no wonder that people soon started finding applications for it beyond optimising listening rooms.

Boiler room noise – gone!

When a tenant complained to their landlord about a disturbing rumbling noise, the landlord did not know what to do. It was clear that the reported noise came from the heat pump located in a small cellar room two floors below the flat, but it was encased in solid wall and closed with a massive door exactly to keep the noise from spilling out. Since the noise was very low at around 50 Hz, the small boiler room acted as a kind of resonator, amplifying the frequency and transmitting it through the solid structures into the entire building. Combating a problem like this would usually take up considerable resources in both time and budget, possibly requiring architectural changes to be made. In comes AVAA: two devices placed in the boiler room eliminated the noise completely, stopping the room from resonating and hence keeping the rumble from spreading through the building.

Peace and quiet for efficient work and recuperation

Another interesting case occurred in a university hospital. New offices had been installed in rooms directly underneath a big machine room containing air conditioning units, cooling systems and other loud machinery. The office workers soon complained about the noise, but what can you do? Both the offices and the machines are required. Expectations were not high when four AVAA C20 were installed for testing purposes – after all, what would those tiny devices be able to achieve against the big motors operating in that room? After conducting a blind test, the answer was clear: the manager would switch the AVAA systems on and off during the day, and the office workers would note when the noise was unbearable. Sure enough, whenever AVAA was active, there were no complaints. Knowing how unnerving and even harmful continuous noise pollution can be, PSI Audio AVAA technology not only helped the office workers, but probably also a number of patients in the hospital who then did not have to put up with some nondescript rumble while trying to heal.

Creating an atmosphere: clubs and restaurants

Restaurants and clubs of any type often put very little effort into their acoustics. The result are places that may look nice and inviting, but where patrons have to shout at each other to understand a word – and the fact that then everyone is shouting does of course not help matters. While mid and high frequency reflexions from naked walls can be an issue, it is often the accumulated low rumble that masks the higher parts of the spectrums with its superior energy levels. This is particularly true when there is a prominent source of music, be it from the radio, a DJ or live bands. Strategically placing AVAA devices in such spaces can significantly improve speech intelligibility and even help with the neighbours, as resonances are suppressed before they can become a serious issue.