Problem
Many rooms often suffer from low frequency modal problems and also
require mid to high frequency reflection control. Absorption
at all of these frequencies has not been possible with a single
acoustical surface treatment of 4" depth.
Solution
The Modex™ Plate solves these problems by offering
significant absorption between 50 and 500hz in a surface depth of only
4". The Modex™ Plate represents a new generation
of acoustic bass management. Now you can absorb more bass in
less space!
RPG is proud to introduce a new and unique addition to the
Modex™ line, called the Modex™ Plate.
Plate was developed by the Institute for Building Physics at the
Fraunhofer Institute, and offers absorption effective from 50 - 5000hz
in a thickness of only 4", The Modex™ Plate has
an attractive powder coated metal finish and can be surface mounted on
walls or ceilings.
Absorption
Surface or corner applied porous materials lose efficiency at low
frequencies, because the particle velocity or air movement associated
with long wavelengths is low. The Modex™Broadband
consists of a freely moving steel plate 1x1.5m sandwiched between
porous layers. Both react together in a mass-spring manner,
offering absorption via three mechanisms. First the plate
provides pistonic absorption down to 50hz by vibrating against the
spring of the porous backing. Second, the bending modes of
the free-moving plate are heavily damped by the proprietary adhesive
coupling with the porous backing up to about 125hz. Lastly,
mid frequency sound waves diffract around the plate edges and through
the perforated sides to be propagated, and thus, dissipated in the deep
passive porous absorber layer. Together, these mechanisms
offer the industries first truly efficient, broad bandwidth low
frequency absorber with a shallow profile of only 4 inches.
Low Frequency testing
Many published low frequency absorption coefficients are nonsense,
because the accuracy of the absorption efficiency decreases at low
frequencies in standard ISO 354 and ASTM 423 tests, due to inadequate
diffusion. Therefore, additional testing has been carried out
at the Fraunhofer Institue in large scale impedance tubes with a cross
section of 1.6m x 1.2m and a special approach monitoring decay times of
the lowest axial modes in a 5x4x3 m room, with and without the sample
present on one of the opposing surfaces.
Installation
The Modex™ Plate is installed by attaching metal 'L'
brackets to the substrate. The panel is then slid over and
screwed to the brackets. Panels should be installed at high
pressure locations. In order of highest to lowest efficiency,
this would be the intersection of three boundary surfaces, two boundary
surfaces and on one boundary surface.
Specifications
Size - 1m x 1.5m x 100mm
Model Name: Plate
weight 70lbs
Finished in white powder coating
predrilled 'L' shaped metal mounting brackets supplied for easy
installation
Features