crystal supports a number of audio elements that can be used to configure monitor source selection and master control. The number of monitor outputs, and their operation, is determined by the configuration.

The rest of this topic describes the monitoring defined in the standard configuration. The operation may vary if the configuration is customized.

Controls Overview

The standard configuration provides three stereo monitor outputs:

  • HP - for the host headphones.
  • CR - for the control room speakers.
  • PFL - for a PFL speaker.

Each output is controlled from the surface as follows. The controls are color-coded for easy identification: green = HP (Headphones); blue = CR (Control Room); green = PFL.

The headphone (HP) controls are always present. The main points of operation are as follows.

  • The large rotary control adjusts the monitor level/balance; turn for level; press down and turn for balance.
  • The surrounding MF keys provide monitor source selection and other options. 

The control room (CR) and PFL controls become available when all of the Function Keys are off. In this instance:

  • The CR rotary control adjusts a single parameter: turn to adjust the output level.
  • For CR, the soft keys provide monitor source selection and other options.
  • For the PFL output, there is a single soft key to clear all active PFLs.

Most of the monitoring functions are operated from the surface. In some cases, pressing a key on the surface opens an overlay box on the GUI. The GUI also provides metering for the CR and HP outputs (via the master slots on the 'Channel Strip' page).

By default, the PFL output is switched automatically to the headphones (HP) whenever a PFL is active. The previous monitor source is re-instated once all active PFLs are cleared. If PFL is selected (as a Control Room monitor source), then PFL is switched to both outputs: HP and CR.

The Control Room output mutes automatically when the Mic Open status is active (i.e. a Mic source fader is open). It can also be muted manually using the Mute CR button.

Audio Connections

The default audio connections are described later in the Standard Configuration Specification. The connections can be edited using the ON-AIR Designer (under "Audio Output → <I/O> Out → Default Audio"). 

If you are running the crystal VX app, then you can use the 'Routing' page (on the GUI) to connect a monitor output to a destination:

  • Select Routing (from the GUI page menu) to open the 'Routing' page.
  • Under 'Sources', select the Monitor Outputs tab and choose a monitor section (e.g. Mon PFL) - the selection flashes in blue.
  • Under 'Destinations', select an output category (e.g. Slot 1) and choose an output (e.g. Line Out 03) - the selection flashes in blue.
  • Press Connect - the connection is made.

Headphone Monitoring (HP)

Monitor Level

The rotary control can adjust two parameters: turn to adjust the first (monitor level); push down and turn to adjust the second (monitor balance).

The display shows the control's function and current value, plus a media icon (to help with identification); output metering (pre-volume); and the current monitor source (e.g. PGM 1).

Monitor Source Selection

For the Headphone output, there are 16 monitor sources available. The current selection lights in green.

The first six sources can be selected directly from the surface: PGM 1, PGM 2, PGM 3, Rec, Aux 1 and On Air. The Soft Select key provides access to the other sources via the GUI (as described later).

By default, the PFL output is switched automatically to the headphones (HP) whenever a PFL is active. The previous monitor source is re-instated once all active PFLs are cleared.

Other Functions

The remaining keys are for other headphone functions:

  • Press Mode to change the monitoring mode (to mono the output, check the phase, etc). This key works in conjunction with the GUI (as described later).
  • Press Split to listen to different signals in the left and right ears of the headphones: left = the selected monitor source (in mono); right = the PFL bus (in mono). You can use this to keep listening to a monitor source (e.g. PGM 1) while cueing up another source.

Using the Soft Select Key

The Soft Select key can be used to listen to a pre-selected monitor source. It works in conjunction with the GUI as follows.

1.    Press and hold the Soft Select key to open the assignment window (on the GUI) - the key turns yellow to indicate that "assign mode" is active.

2.    Choose an option using the on-screen buttons and then touch X to close the window.

3.    Press the Soft Select key quickly to monitor the assigned source - the key turns green to indicate that the monitor source is selected.

The current selection is stored in the system's warm start data. This means that the Soft Key monitor source is reinstated after a restart, unless you perform a cold start.

The 16 monitor sources are defined by the configuration. See Standard Configuration Specification for details.

Using the Mode key

The Mode key can be used to mono the monitor output, check the phase, etc. It works in conjunction with the GUI as follows.

1.    Press the Mode key to open the HP mode options (on the GUI).

2.    Choose an option using the on-screen buttons and then touch X to close the window.

The following options are possible (and options may be combined except for Left to Both, Right to Both and Side).
  • Mono - the left and right inputs are summed with a -3dB gain offset.
  • L→B - the left input is routed to both sides of the matrix.
  • R→B - the right input is routed to both sides of the matrix.
  • Phase - reverses the phase of the left input.
  • Side - the left input and right inputs are reversed (left input to right side of matrix, and right input to left side of matrix).

The current selections are stored in the system's warm start data. This means that the HP Mode is reinstated after a restart, unless you perform a cold start.

Control Room Monitoring (CR)

For the Control Room (CR) output, the rotary control adjusts a single parameter: monitor level. The display shows the control's function and current value. The current monitor source is highlighted in blue (e.g. PGM 1).

There are two monitor source select keys: PGM 1 or Soft. The Soft select key works in the same way as for the HP output: press and hold to pre-select a monitor source (from the GUI); press quickly to monitor the assigned source. 

The Mode key can used to mono the output, check the phase, etc. It works in the same way as for the HP output: press to open the CR mode options (on the GUI) and choose an option.

The Control Room output mutes automatically when the Mic Open status is active (i.e. a Mic source fader is open). It can also be muted manually using the Mute CR button (above the HP monitor section).

PFL Monitoring

In the standard configuration, the PFL output is switched automatically to the headphones (HP) whenever a PFL is active. The previous monitor source is re-instated once all active PFLs are cleared. If PFL is selected (as a Contol Room monitor source), then PFL is switched to both outputs: HP and CR. 

If Split is active, then you will hear different signals in the left and right ears of the headphones: left = the selected monitor source (in mono); right = the PFL bus (in mono). You can use this to keep listening to a monitor source (e.g. PGM 1) while cueing up another source.

The Mon PFL output can be connected to a separate PFL speaker, either by editing the default audio connections (using ON-AIR Designer) or by making a connection from the 'Routing' page (on the GUI).

You can use the PFL controls (at the top of the Main module) to check that signal is present and Clear all active PFLs.