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QRD 734 - RPG Diffusor

QRD 734 - RPG Diffusor
Product Code: GRG QRD
Availability: Contact Us POA
Download Description: For Registered Users Only
Price: Request Quote

RPG QRD 734 Diffusor

  • Quadratic residue sound diffusion
  • Recording studios
  • Practice rooms
  • Home theatres
  • Mastering studios.
  • Wood finish, paintable finish
  • Can be surface or flush mounted
  • Can be oriented to provide two-dimensional diffusion in the far field
  • Attractive finish
  • The wide bandwidth, low cost, and broad selection of finishes make this diffuser a logical choice for music education facilities, recording studios, worship spaces, auditoriums, theatres, and performing arts facilites.
  • This one dimensional diffuser is a modular, computer designed phase grating which produces a directional hemidisc polar response that can be oriented in any direction.
  • It also provides low frequency absorption below the design bandwidth due to the RPG pressure gradient mechanism.

Interfering reflections that degrade speech intelligibility, gain before feedback, and music quality can be controlled by absorption and diffusion. Since commercial surfaces that provided uniform diffusion over a wide frequency range and for all angles of incidence were not available, absorption was used solely to control reflections. This treatment created 'dead' spaces.

The QRD 734 is a quadratic residue acoustic diffuser based on mathematical number theory. Now a predictable diffusive surface treatment is readily available.


Options are: Paint ready (primed), 2 coat paint, 2 coat varnish, plain MDF, Beech, Ash, Oak, Maple and Cherry.  


Compared to a flat reflector panel, the QRD 734 offers significant diffusion above the diffraction limit of 565Hz, which is equal to the speed of sound (1130ft/sec) divided by the 2' dimension of the panel. As the frequency increases above 565Hz, a reflector becomes more and more specular, whereas the QRD 734 provides a uniform diffusivity. Diffusion starts at around 320Hz


The wooden QRD® 734 contributes minimal absorption.


The QRD 734 is typically mounted on a cleat and secured. For installations that require a flush mount the units should be framed out much like an opening for a window.

RPG QRD Diffuser panel in home cinemaRPG QRD Diffuser panel in recording studioRPG QRD Diffuser panel in live room 

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