Ducking is a common technique used in radio and television broadcasting:  When the DJ or announcer speaks while music is playing, the music level is automatically reduced. When the announcement has finished, the music is automatically raised to its original volume level.

Ducker provides a simple means of achieving this result with existing recordings. It does not work in real time.

Note: For technical reasons, Ducker can only be inserted in output and aux channel strips.

Ducker Parameters

The Ducker has the following parameters:

Figure. Ducker window.
  • Ducking On and Off buttons: Enable or disable ducking.
  • Lookahead On and Off buttons: Enable to ensure that the Ducker reads the incoming signal before processing. This results in no latency—it is primarily intended for slower computers.
  • Amount slider and field: Defines the amount of volume reduction of the music mix channel strip, which is, in effect, the output signal.
  • Threshold slider and field: Determines the lowest level that a side-chain signal must attain before it begins to reduce the music mix output level—by the amount set with the Intensity slider. If the side-chain signal level doesn’t reach the threshold, the music mix channel strip volume is not affected.
  • Attack slider and field: Controls how quickly the volume is reduced. If you want the music mix signal to be gently faded out, set this slider to a high value.

    This value also controls whether or not the signal level is reduced before the threshold is reached. The earlier this occurs, the more latency is introduced.

    Note: This only works if the ducking signal is not live—the ducking signal must be an existing recording. The host application needs to analyze the signal level before it is played back in order to predefine the point where ducking begins.

  • Hold slider and field: Determines the duration for which the music mix channel strip volume is reduced. This control prevents a chattering effect that can be caused by a rapidly changing side-chain level. If the side-chain level hovers around the threshold value rather than clearly exceeding or falling short of it, set the Hold parameter to a high value to compensate for any rapid volume reductions.
  • Release slider and field: Controls how quickly the volume returns to the original level. Set it to a high value if you want the music mix to slowly fade up after the announcement.

Using the Ducker

The steps below show how to use the Ducker on existing recordings.

Note: For technical reasons, the Ducker plug-in can be inserted only in output and aux channel strips.

To use the Ducker plug-in
  1. Insert the plug-in into an aux channel strip.

  2. Assign all channel strip outputs that are supposed to “duck” (dynamically lower the volume of the mix) to a bus—the aux channel strip chosen in step 1.

  3. Choose the bus that carries the ducking (vocal) signal in the Side Chain menu of the Ducker plug-in.

    Note: Unlike all other side-chain-capable plug-ins, the Ducker side chain is mixed with the output signal after passing through the plug-in. This ensures that the ducking side-chain signal—the voice-over—is heard at the output.

  4. Adjust the Ducker parameters.