Various - qrd - the guitarists

When a QRD panel is used stand-alone , the phase shifts introduced by the wells produce concentrations of energy in given directions. The interraction of these produces a complex diffusion field that becomes increasingly difficult to model as the number of wells is increased. The QRDude calculator shows a 'scattering' drawing to help visualise this, but doesn't compute the actual angles.

Single panels are of use, but QRDs are meant to be used in arrays of multiple panels...

When multiple panels are used, constructive and destructive reinforcement between the reflections from each panel produces lobes of concentrated energy at known angles.
These lobes take precedence over those generated by the individual panels, and can be computed.

The QRD formula ensures that these lobes are of equal energy at multiples of the design frequency. These special frequencies can be thought of as the "true diffusion" frequencies. At other frequencies, the lobes will vary in intensity. It is this 'equal energy' aspect that is the QRD's main claim to fame.
The QRDude calculator has a Lobes screen that allows these lobes to be modelled for incoming signals at varying angles.

Various - QRD - The GuitaristsVarious - QRD - The GuitaristsVarious - QRD - The GuitaristsVarious - QRD - The Guitarists