The shape of contoured acoustic foams makes relatively little difference to its noise attenuation.
This was a surprise conclusion to a paper presented by Pyrotek Noise Control ’s Technical Manager, Michael Latimer at the 20th International Congress on Acoustics (ICA) held in Sydney late last year.
Michael shared the honour of co-chairing conference sessions on architectural acoustics with his brother, Richard Latimer, Pyrotek’s Marketing Manager, who also presented a paper on a new type of porous sound absorber.
Written with colleagues from the Department of Mechanical Engineering at New Zealand’s University of Canterbury, Michael’s paper reported on investigations into some common practices and assumptions about foam absorbers. The work particularly challenged the belief that foam with surface shapes, such as pyramids and corrugations, absorbs more sound due to the greater surface areas.
However, Michael’s research showed that the shape of the foam made little difference and that the thickness of the foam was a more important factor. It also showed that painting the foam changed sound absorption only slightly and that fabric covers do provide a useful increase in absorption.
The subject of Richard Latimer’s paper was a new porous sound absorber, Reapor. The paper described how the product combines two existing common technologies (cellular and fibrous absorbers) using recycled glass which is formed into beads and bonded into a panel. This results in a range of benefits including high sound absorption in a product that is non-combustible, rigid, durable, a hundred percent recyclable and quick to install.
Commenting on their role in the ICA, Richard said, “The technical program was of a very high standard and both papers were very well received, giving Pyrotek Noise Control great exposure on the world stage.”
The ICA is held every three years and provides the opportunity for the world’s leading acousticians to meet and share their expert knowledge.
