Optistep Feature Image2


The Optistep is a 1-dimensional sound diffuser developed to expand the product line anchored by the classic QRD 734 – the first product of its kind offered on the market.  With its unique design which does not rely on the traditional dividers between each well, the Optistep has been designed to offer optimal diffusion bandwidth, while the natural wood construction of the unit limits the amount of sound energy that is removed by absorption.


The Optistep is available in a wide variety of finishes, including wood veneer, laminates, melamine coatings and painted surfaces.


The Optistep is flush or cavity mounted to walls and ceilings with provided blocking.

Optistep is a Trademark of RPG Acoustical Systems LLC



To minimize the lobing inherent in traditional sound diffuser designs, which compromises the uniformity of the scattering, RPG developed the Optistep. The Optistep offers significantly better performance due to it’s large sequence of element depths. Where the performance difference advances further is when multiple units are installed in an array. An optimized, modulated sequence of an array can take advantage of the aperiodic, asymmetric shape of the Optistep to minimize lobing effects that are caused by symmetrical and periodic shapes. In contrast to a QRD periodic array, an Optistep aperiodic array is formed by following the prescription of an optimal binary sequence, which indicates when to use the asymmetric base shape (zero) or the rotated unit (one). The Optistep is available in a wide variety of finishes, including wood veneer, laminates, melamine coatings and painted surfaces. It is designed to fit into a standard, reinforced T-Bar grid; more often, it is flush mounted to a wall or ceiling with the included mounting cleat.


Interfering reflections that degrade speech intelligibility, gain before feedback, and music quality can be controlled by absorption and/or diffusion. When absorption alone is used to control reflections it creates “dead” sounding spaces that lack the benefit of late order, high frequency reflections which can greatly enhance the acoustic performance of a space. Quadratic residue diffusers (QRDs) are the most common type of sound diffusers on the market, and owe their sound diffusing ability to the phenomenon of diffraction from a periodic reflection phase grating. To cover wide areas, the units have to be repeated in a periodic fashion. This periodicity decreases the attainable uniformity, reducing its performance as the width of the array increases.


To solve this problem, RPG developed a new optimized sound diffuser called the Optistep. The Optistep embodies two patents; Shape Optimization and Aperiodic Modulation of a Single Asymmetric Base Shape. This optimized asymmetric surface is now capable of being arrayed in an aperiodic manner, using optimal binary sequences. This offers a significant performance advance over QRD designs.


  • Offers broad bandwidth sound diffusion in a decorative, wood cabinet.
  • Multiple unit arrays can be sequence optimized for further improvement in scattering.
  • Comes in a variety of finishes, including wood veneer, laminate, melamine and custom paint colors.
  • Comes standard 8″ depth; can be customized for either shallower or deeper units.
  • Simple installation with included mounting cleat.

RPG Wood Products can be manufactured to match most commercially available and custom wood veneers.

Common Wood Species

Ash 1

Stocked product samples are typically manufactured using common wood species – no products are available at any one time in all of the above species. Please check with your local rep or contact RPG.