Background
Contacted by Dynamic, iKoustic was brought in to help design and implement our range of Sound Absorption materials to improve the internal sound quality of the room by reducing the great reverberation levels.
As an open-truss space, it created a high and airy environment – it’s beautiful exposed beams would need to be kept as part of the building’s interior image.
Control of lighting was also a key factor through the additional use of the room in filming; we have included our bespoke option for this in our solutions below.
Dynamic provides e-learning, application design and development to their customers and intend to use this room as a multi-media space, using it to carry out audio/visual work for their customers in the way of filmography – you can read more about what they do here: http://dynamicbusiness.co.uk/what-we-do.php.
The room featured a carpet tile flooring with the rest of the walls and pitched ceiling area constructed of dense, hard and reflective materials that cause a long reverberation time to appear in a room, especially of this size.
| Length | Width | Height |
| 10.95m | 7.05m | 4.74 (to apex) |
The use of this room for audio recording meant that the reverberation levels had to be massively reduced to allow for a clear as a possible audio signal that wouldn’t be coloured by the effects of this room.
Our initial calculations put this space in the region of 3.09 seconds, which is less than desirable for audio recording spaces.
The adverse soundscape had made the space almost unusable, with audio recordings taken in abstract methods.
Reverberation and how it affects Speech Intelligibility
Speech intelligibility is very important, especially when clear, concise instructions being given for example; through teaching. It is also crucial in filmography. A highly reverberant room affects the sound quality and understanding of speech, as late reflections are still being picked up with a conversation that is a few seconds ahead will confuse, and a lack of concentration will ensue.
“A classroom with long reverberation time of several seconds will cause syllables to be prolonged so that they overlap and hence degrade speech intelligibility. Long reverberation times occur in large rooms with hard wall and ceiling surfaces, adding acoustic absorption and reducing the ceiling height will reduce the reverberation time and will improve speech intelligibility.”
– An excerpt from BB93.
Although this quotes guidelines for desired acoustic levels in schools, it is still very much applicable universally. It is essential to retain the highest level of speech intelligibility in any recording of voice-overs or film so that you avoid loss of engagement.
Solution
Our solution was to acknowledge the reverberation issues of the room that hinder it’s intended use and put together ways the client could keep the impact of the sound absorption material on the build minimal, as well as giving them the control to adjust the amount of reverberation in the room (as some cases may require a slightly longer decay), and creating temporary vocal booths.
All materials needed to have minimal impact on the building, so we did not opt for any adhesive options as a direct fit to walls or ceilings. We needed to look at small hooks and gripples to extend down in the vast space, and implementing free-standing panels that mobile.
The solution also needed to be only in white; this was so that any light in the room would not be influenced by the colour of the sound absorption, thus affecting the video capture on film. The customer also required control over the light in the room, so we created a form of Bespoke Window Plug from cut out of a sound absorption panel, and a fitted handle so it can be easily removed – this was to act as a triple effect on soundproofing from external noises, further sound absorption and satisfy controlling the brightness.
We also needed to take into account the height of some of the actors, some at the elevation of 6 ft “9, so all the hanging materials required to be at level If possible with the rafters.
Proposed Layout
Option 1 with Adagio
Option 2 with Octave
Results
With our last drafted ideas in the solution, and responding to the customer and their design favourite, we implemented the following iKoustic materials into the space.
| 3D Note™ Adagio | Window Plug (Bespoke) | Soft Note™ 50mm |
| 6 | 5 | 6 |
Our video shows a tremendous audio example of our Voice Over in the room in the same space as a before and after the test, but in figures, this is displayed below.
| Before | After |
| 3.09 seconds | 0.85 seconds |
After these fantastic results, the team at Dynamic are now able to use the space as they intended it.