The Nimbus is, in many ways, the ideal acoustical device. It absorbs energy via the front panel; absorbs energy from the rear side; easily mounts from the ceiling where it is out of the way of windows, doors, and art; and it quietly goes about its job, reducing stress in the workplace and improving intelligibility for those that wish to communicate.
The term ‘intelligibility’ refers to one’s ability to understand or comprehend what is being said in a given room. For instance, everyone knows how unpleasant it is to go to a restaurant that is so ‘loud’ that it makes having a conversation impossible. The reason for this is simple; as more and more people converse, the hard surfaces of the walls, glass and tables reflect the energy back into the room where it echoes without any means of escape. Outside, sound is lost into space as there are no reflective boundaries. In the restaurant, as the ambient sound level increases, people naturally speak louder in order to be heard above the din. The louder we yell, the worse it gets. And if you are like me, you simply do not go back.
But this problem is not limited to restaurants. Hotel lobbies, airports, gymnasiums, classrooms… all of these spaces suffer from the same problems. And then when announcements from the PA are dispatched, they are impossible to understand. The solution is simple: introduce some form of absorption into the space.
The science built into the Nimbus is simple: sound - in the form of vibrations – passes through the acoustically transparent fabric and penetrates fine glass wool filaments causing them to vibrate. This is known as a thermo-dynamic transfer whereby acoustic energy is transformed into heat.
The absorption performance of the two inch thick Nimbus is remarkable when compared to two inch urathane foam. Unlike foam panels that have virtually no effect in the lower mid range where the human voice tends to sound "boomy" the Nimbus delivers 90% efficiency.
The added benefits of suspending the Nimbus to create a an air space behind the panel are remarkable. With the Nimbus suspended a few inches below the ceiling the sound not only penetrates the front face of the cloud, but as sound echoes off the room walls, some of it will be absorbed by the back side too. This simple trick of exposing more surface area can double the performance of an acoustic cloud like the Nimbus.
The overall low frequency absorption performance is further augmented by the air-space behind the panel. The air space behind panel acts like a bass trap, effectively increasing the low frequency absorption. In fact if you create a 12" (30cm) air space behind the Nimbus, you will likely enjoy as much as an extra octave of low frequency absorption for free. Free is always good!
The Acoustic Bell Curve
For the most part, the science of acoustics is really based on good old fashioned common sense. And although this may seem obvious, you need to start with the notion that the more acoustic panels you put in your room, the more energy you will absorb. This in itself makes solving the problem easy: put a single panel up in a gymnasium and nothing will happen. Put a million panels up and you will no longer have any echo.
The acoustic bell curve basically presents this concept in a graph whereby the X line shows the number of panels hence cost, while the Y shows effectiveness. At one point along these lines, you will find the acceptable balance to suit your needs. For instance, if you want to keep some ambiance in the restaurant, then maybe apply 10% absorption. If, on the other hand, you want your hotel lobby to be quiet, you may want to apply 35%. There is no rule that says you cannot start with some panels and add more as you go. In fact most folks start by looking at what wall space and ceiling space they have, and then combine Broadway wall panels with Nimbus ceiling clouds to create a balance that works for them.