For years, acoustic clouds and canopies have been used to control sound. They can be made of ridged material to reflect sound waves or soft material to absorb it depending on their purpose. In theatres, reflective clouds are often visible in the form of hard, curved devices that are arrayed and suspended above the stage. Theatres use theses types of clouds to reflect sound back toward the stage so that the musician can get a sense of intimacy. These reflective type acoustic clouds provide the natural ambience of a smaller room within a cavernous hall, thus allowing the performer to better interact within the acoustic environment. Absorbing acoustic clouds, like the Primacoustic Stratus, perform the opposite function: instead of reflecting energy back into the space, the absorbing properties are used to remove unwanted reflections. Basic forms of these devices are known as acoustic baffles (or flags) and are often used in highly reflective environments such as swimming pools, bottling plants, printing presses, and other commercial installations where controlling echo or reducing the reverberant time can make the workplace a more comfortable and safe place.


This theater uses reflective clouds to help send sound from the stage back into the space.


This dance studio uses absorbing clouds to cut down the room’s reverberation time.

The Primacoustic Stratus is a more elegant solution and is the preferred choice in environments such as recording studios, where acoustic performance is as important as aesthetics. Acoustic clouds play an important role in studio design as they control the powerful primary reflections that originate from the monitors and bounce off the ceiling and console. These primary reflections combine with the direct sound of the loudspeaker and cause phase cancellation. Furthermore, parallel surfaces such as a floor and ceiling cause standing waves to exist which can introduce a resonant peak in the primary listening area.

When the effects of phase cancellation and standing waves are pronounced, the engineer will naturally attempt to fix the sound using tools such as an equalizer on a given instrument. The result will be a tonal shift that may sound OK in that room, but when the program material is heard in another location, the missing frequencies may all of a sudden become apparent.

By controlling the listening environment around the mix position, anomalies such as primary reflections, standing waves and flutter echo are greatly reduced. This allows the engineer to make better decisions while mixing, as what they are hearing is not coloured as much by the room acoustics. That translates into better sounding tracks with more consistency from one listening environment to another.

This is easily done by hanging Stratus cloud kits above the listening area. Primacoustic Stratus kits include linking hardware allowing as many Stratus kits as necessary to be arrayed over the listening position. One should also consider treating adjacent walls around the mix position to control unwanted side to side reflections using Broadway acoustic panels.


There are many ‘makeshift’ options to create an acoustic cloud. These can be as simple as hanging Broadway panels using eye-hooks and wire, to more elaborate methods like building a wood frame to support several Broadway panels. Both will do the job. The Stratus simply offers a more elegant solution that is ‘modular’ in concept allowing it to adapt to varying room sizes. The light weight aluminum frame offers several suspension points for quick installation, or may mount directly to the ceiling. Because the system is designed to be expanded, a more uniform and attractive installation will result. This means that those that are not skilled carpenters can enjoy wonderful looking results in any room.