Using Surround Panners to Create a Surround Mix

The following sections explain how to use the surround panners in Soundtrack Pro to create a surround mix. The surround panners provide a straightforward and flexible way to control and monitor panning settings. By changing the panner type in the track header, you can easily switch any track or bus from stereo to surround, or from surround to stereo. Soundtrack Pro offers two different versions of the surround panner: the mini surround panner and the surround panner HUD.

The Mini Surround Panner

Use the mini surround panner to switch between stereo and surround mixing, to make simple surround adjustments, and to quickly check the pan setting for a track or a bus.

To switch the panning controls from stereo to surround
Do one of the following:
  • Select the track or bus, then choose Multitrack > Use Surround Panner.

  • Control-click the stereo pan slider in the track header, then choose Use Surround Panner from the shortcut menu.

    Figure. Track header shortcut menu.

The surround panner replaces the stereo panner. This is the smaller of two different views of the surround panner. To use the larger Surround Panner HUD, see The Surround Panner HUD.

Figure. Surround panner in a track header.

The Surround Panner HUD

The Surround Panner HUD offers finer panning adjustments, a graphic representation of the current surround setting for the selected track, and other surround controls.

To display the surround panner HUD
Do one of the following:
  • Double-click the surround panner in the track header of the track or bus you want to adjust.

  • Double-click the surround panner in the Mixer channel strip of the track or bus you want to adjust.

The surround panner HUD appears in a floating window over the Soundtrack Pro window.

The dominant feature of the Surround Panner HUD is the black circle that represents the virtual surround space. The puck, a dot inside the circle, is the primary surround pan control. Input channels are represented by color-coded, semi-circular, translucent arcs emanating from the inside of the circle’s circumference. These arcs indicate the input channel’s gain (by the height of the arc), the channel’s spread (by the width of the arc), and location. Overlapping sounds are represented by overlapping arcs, summing (combining) to white where all channels overlap.

Figure. Surround Panner HUD, showing puck, rotation slider, width slider, collapse slider, center bias slider, and LFE balance slider.
  • Position: The puck is the main control in the panner. To pan the audio, move the puck by clicking anywhere inside the black circle or by dragging the puck to a different position in the circle. The speaker icons around the edge of the circle represent the five main surround channels: L (left), C (center), R (right), Ls (left surround), and Rs (right surround). The closer you move the puck to one of the speaker icons, the louder the sound will be from that speaker. For more information about moving the puck to adjust the position parameter, see Modifier Keys for Moving the Puck.

    Note: In automation envelopes, this Position parameter is expressed as Surround Pan X and Surround Pan Y.

  • Rotation: Use this slider to alter the angle at which each signal starts out. This slider ranges from -180 degrees to 180 degrees and affects the input signal. For example, with no other panning, the right channel emanates from a location 45 degrees to the right. With rotation at +65 degrees, the signal appears at 110 degrees—directly out of the right surround speaker.
    Figure. Surround Panner HUD showing how relationship between signal start angle and rotation slider.

    Note: This setting interacts with the position parameter when the panner mode is not fully attenuating.

  • Width: Use the Width slider to create a widened surround image. This slider is intended primarily for stereo sources in that it spreads the left and right inputs into adjacent channels. This creates the illusion of a widened sound stage without the hole at the center that moving the puck rearward would create. For some movie theaters, it may be necessary to use the Width slider to bleed the center signal in to the left and right speakers. At 0%, all inputs go to their respective outputs. As you drag the Width slider to the right, L and R inputs start to bleed into Ls and Rs respectively, and to a lesser extent, L and R bleed into C, C bleeds slightly into L and R, and Ls and Rs start to merge.
  • Collapse: Typically, panners are either of a collapsing style (panning folds input signals into output speakers) or an attenuating style (panning simply turns down the gain of speakers further from the pan location). The Collapse slider goes from a fully attenuating style, through a hybrid style, to a fully collapsing style. At full attenuate (0% on the slider), no input bleeds to any other output; each channel remains at its original speaker position. The only change is to output gain. At full collapse (100% on the slider), no input gain is changed—instead, inputs have their output divided over adjacent channels. At 50%, a given input channel panned away has its input attenuated by 50% and distributed between the two adjacent channels.
    Figure. Three Surround Panner HUDs showing Collapse set to 0, 50, and 95.
  • Center Bias: Use this slider to determine how the center channel interacts with the left and right channels. At 0%, all sound that would have gone to the center speaker is equally distributed to the left and right speaker. At 100%, the center is used fully, just like any other speaker. This means that if you move the puck directly in front of the center speaker, all sound emanates exclusively from that speaker. If you move the puck halfway between the center channel and an adjacent channel (yet still on the perimeter of the black circle), the sound is equally and exclusively divided between those two speakers.
  • LFE Balance: Use this slider to balance control between LFE and the other five channels. At -100, nothing is output from the LFE speaker, even if there was LFE input, and all other channels pass through at unity gain. At its midpoint (0), all six channels pass through at unity gain to their respective speakers, meaning that LFE input passes directly to LFE output. At +100, all six signals get summed to the LFE speaker.
  • Speaker Disable: Click a speaker icon once to turn it on or off. If you turn off a speaker, its output goes to adjacent speakers. Each speaker supports a single-click on/off for that speaker’s output.
    Figure. Surround Panner HUD showing active and inactive speakers.

Surround Panner Automation

Automating surround pan settings is very similar to automating stereo pan settings: a track or bus set to use the surround panner has at least seven different panning envelopes, and a stereo track or bus has only one pan envelope. Automation for the Position parameter (the puck) is reflected in two envelopes: Surround Pan X and Surround Pan Y. These are Cartesian X & Y values referring to the puck position within the black panning circle. All other surround panning parameters are expressed with one envelope each, except for Collapse and Speaker Disable, which cannot be automated. For more information about automation, see Working with Automation.

Modifier Keys for Moving the Puck

Hold down any of the following keys as you move the puck to constrain its movement. These modifier keys offer finer control as you make adjustments to the position parameter.

  • Shift: Fine adjustment
  • Option-click: Reset control
  • Option-drag: Straight movement, restricted to diversity, constant angle
  • Command: Circular movement, restricted to angle, constant diversity
  • Command-Option-drag: Restricted to either X or Y movement

Surround Metering

Soundtrack Pro provides a variety of level meters to monitor output levels as you make surround panning adjustments.

Surround Panner HUD Meters

The Surround Panner HUD includes level meters that show volume information from the specific track or bus that you are panning. These meters can be hidden or displayed by using the disclosure triangle. Track-specific meters are a useful reference given the possible psychoacoustical “illusions” in surround mixing, such as the phantom center.

Figure. Surround Panner HUD.

Meters Tab

The Meters tab displays levels for the current multitrack project. The channels displayed in the Meters tab and in the Mixer meters (described in Mixer Meters) depend on the audio interface connected to your computer, the current panner settings, and the current output settings in System Preferences.

For more information about output settings, see Connecting Physical Outputs.

Figure. Meters tab showing 2-channel and 6-channel meters, showing level meters, Reset button, and Peak Value and Location display.

Mixer Meters

Each channel strip in the Mixer includes a levels meter capable of displaying up to all six channels. The Mixer is the only place you can view the levels for each track, bus, and submix as well as the Master bus.

Figure. Channel strip showing a 6-channel meter.