GEQ

A 28-band 1/3 octave Graphic Equaliser is provided on each of the 20 mix outputs. It can be adjusted using the touch screen or the surface faders.

Frequency response curve – The top part of the screen shows the combined response of the slider settings. This can show the response differences between the four GEQ types available.

RTA display – The Real Time Analyser display is superimposed on top of the frequency response curve. The RTA displays metering of the currently selected PAFL signal split into its 1/3rd octave frequency bands. The meter bars are shown in green. A red bar indicates the dominant frequency band if the Show Peak Band option has been set in the Meters / RTA screen Options pull-up window.

Note The RTA follows the current PAFL selection. Make sure you have selected the PAFL key for the channel or mix you wish to analyse, for example the related Aux mix when you are using the GEQ and RTA to ring out a stage monitor.

Using the screen to control the GEQ

Touch a frequency slider to highlight it. Drag the slider with your finger or use the screen Rotary to adjust cut or boost for the highlighted frequency band.

In - Switch the GEQ in or out of circuit. The settings turn yellow when switched in and grey when switched out.

Sel button – Touch and hold to listen to the signal after the GEQ. This interrupts the current PAFL selection in the headphones and listen wedge/IEM monitor. Touch while holding the Copy, Paste or Reset key to copy the GEQ settings to other mixes or to reset all bands flat.

GEQ Type – Use the drop-down menu to select one of four GEQ types available. These offer different types of cut/boost response:

Constant-Q - Symmetrical cut/boost where the width (Q) of the filter is a constant 1/3rd octave for any amount of cut or boost.

Proportional-Q - Provides smooth wide Q for low cut/boost, which progressively tightens beyond 1/3rd octave for max boost/cut.

Digi-Q - Gain and width are optimised to minimise band interaction and to provide a frequency response as close to the slider positions as possible.

Hybrid - Allen & Heath have developed the best of both worlds. The boost is proportional-Q for smooth and warm small boost settings. The cut is Constant-Q providing clinical 1/3rd Octave attenuation with minimal band interaction.

Using the faders to control the GEQ

You can quickly access the GEQ on the faders for the mix with its Sel key active by:

• Touching the screen GEQ Fader Flip button, or
• Pressing the GEQ Fader Flip key to the right of the faders while in any of the mix Processing pages.

This puts the lower frequency half of the GEQ on to the faders. Press again to present the higher frequency half, and press again to return to normal fader mode.

The frequency values are shown in the strip LCD display which turns red while in Fader Flip mode.

In Fader Flip mode the extreme right hand strip becomes the Master for the mix currently selected. The fader is either the mix master or a channel send to that mix if a channel Mix key is active. This lets you ring out a monitor mix by adjusting the GEQ while raising the channel send rather than master using this fader.

Press the fader strip Sel keys to reset individual frequency bands flat. The green Sel indicator lights when the band is flat.

Selecting the mix PAFL key and using the RTA Show Peak Band option will let you see the RTA on the strip meters and help you identify frequencies that start to ring.

Library - You can store and name the current GEQ settings as a preset in the Library. Existing presets can be overwritten with the current settings. User Libraries can be exported and imported via USB key. To do this go to the Setup / Memory / Library Manager screen.

Note The GEQ Type is stored as part of the GEQ Library.