
QRD 734
Overview
The QRD 734 has become a classic shape in architectural acoustics, from its birth in 1987 it can now be found in churches, schools, theaters and studios all over the world. The surface of the QRD 734 is designed to provide a more uniform sound field through mid and high frequency diffusion while the natural wood construction of the unit limits the amount of sound energy that is removed by absorption.
Finish
The QRD 734 is available in a wide variety of finishes, including wood veneer, laminates, melamine coatings and painted surfaces. See some of the options displayed under the Finishes tab below.
Installation
The QRD 734 is designed to fit into a standard, reinforced T-Bar grid. More often, is it flush mounted to a wall or ceiling with appropriate blocking. Due to it’s depth, it is often recessed into a wall or ceiling cavity. See details below under the Drawings tab.
QRD is a Registered Trademark of RPG Acoustical Systems LLC
QRD 734 1D Wood Sound Diffuser

The phase grating surface of the QRD 734 is designed to provide a more uniform sound field through mid and high frequency diffusion while the natural wood construction of the unit limits the amount of sound energy that is removed by absorption. It has become a classic shape in architectural acoustics; from its birth in 1987 it can now be found in church, theater and recording studio spaces all over the world. Its wide bandwidth, low cost, and broad selection of finishes also make it a logical choice for music education facilities, auditoriums and performing arts facilities.
The QRD 734 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.
Problem
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 reflections which can greatly enhance the acoustic performance of a space.
Solution
The QRD 734 is first and most applied sound diffusing panel in the world. Rather than remove the energy that strikes key surfaces in a space, the QRD preserves the energy by uniformly distributing the energy back into the space. The onset of diffusion for the QRD 734 occurs at roughly 320 Hz.
Features
- Offers broad bandwidth sound diffusion in a decorative, wood cabinet.
- Comes in a variety of finishes, including wood veneer, laminate, melamine and custom paint colors.
- Comes standard 9-1/8″ 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
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.