10.6

99Logic Pro Effects
The interface is divided into three sections:
• The Link section at the top contains menus used to assign each channel to a group.
See Logic Pro Surround Compressor Link parameters.
• The Main section includes controls common to all the main channels and the threshold
and output controls for each channel. See Logic Pro Surround Compressor main
parameters.
• The LFE section on the lower right includes separate controls for the LFE channel.
See Logic Pro Surround Compressor LFE parameters.
Logic Pro Surround Compressor Link parameters
Surround Compressor Link parameters provide grouped channel control.
Link parameters
• Circuit Type pop-up menu: Choose the type of circuit emulated by Surround
Compressor. The choices are Platinum, Classic A_R, Classic A_U, VCA, FET, and
Opto (optical).
• Group pop-up menus: Set group membership for each channel—A, B, C, or no group
(indicated by -). Moving the Threshold or Output Level slider for any grouped channel
moves the sliders for all channels assigned to that group.
Tip: Press Command and Option while moving the Threshold or Output Level slider
of a grouped channel to temporarily unlink the channel from the group. This lets you
set independent threshold settings while maintaining the side-chain detection link
necessary for a stable surround image.
• Bypass buttons: Bypass the channel. If the channel belongs to a group, all grouped
channels are bypassed.
• Detection pop-up menu: Choose the signal type to exceed or fall below the threshold.
Max uses the maximum level of each signal. Sum uses the summed level of all signals.
• If Max is chosen and any of the surround channels exceeds or falls below the
threshold, that channel (or group of channels) is compressed.
• If Sum is chosen, the combined level of all channels must exceed the threshold
before compression occurs.