Setting Channel Strip Levels

You are probably familiar with setting and adjusting channel strip levels, from creating your arrangement. You set and adjust channel strip levels, several times during the mixing process, to control the volume relationships between your project’s parts.

When setting channel strip levels, you use the following channel strip elements:

Figure. Channel strip with peak level display, Volume fader, and Level meter.

Note: Metering plug-ins—such as the Level Meter—are also available if your needs extend further than the channel strip controls.

Understanding a Channel Strip’s Peak Level Display

The peak level display is a numerical display located above the level meter.

Figure. Channel strip with peak level display.

It updates during playback to show the peak level reached. The peak level display shows the highest peak level after the entire signal has been played through to the end, and provides a guide that should be used to set the Volume fader.

Signal clipping occurs when too loud a signal is fed through the output channel strip, thereby exceeding the limit of what can be accurately reproduced, resulting in distorted sound. When a signal clips, the value shown in the peak level display is highlighted in red.

Figure. Channel strip with peak level display showing signal clipping.

Note: It is not a problem if individual channel strips show evidence of clipping, as long as the output channel strip (which is the summed level of all channel strips in the signal flow) does not indicate clipping.

To eliminate clipping, you need to bring down the Volume fader by the same value that is shown in red in the peak level display. For more information, see Using a Channel Strip’s Volume Fader.

To reset all clip indicators
  • Click any clip indicator (or use the “Clear Overload Flag in Audio Channel Display” key command).

Using a Channel Strip’s Volume Fader

You use the Volume fader to set a channel strip’s volume level.

Figure. Channel strip with Volume fader.
To set the volume level of a channel strip
  • Drag the channel strip’s Volume fader up or down.

The maximum boost is +6 dB. You can reset the Volume fader to 0 dB (90) by Option-clicking it.

Note: If the “Independent Monitoring Level for Record Enabled Channel Strips” checkbox is selected (in the Core Audio pane of the Devices pane of Audio preferences), an independent monitoring level is available when an audio channel is record-enabled. For more information, see Setting the Monitoring Level for Recording.

To avoid clipping
  1. Check the red value shown in the peak level display of the channel strip, which indicates clipping.

    In the figure below, 1.7 dB is shown in the clip indicator when the Volume fader is set to a value of 2.2 dB.

    Figure. Channel strip with peak level display showing signal clipping.
  2. Drag the Volume fader down to a value of 0.5 or so.

Tip: You may find, however, that a Volume fader value of −1.2 sounds best in the context of the overall mix, and clips only once (by 0.3 dB) during playback. If this is the case, it is nothing to worry about. Use your ears rather than your eyes as a guide.

Understanding a Channel Strip’s Level Meter

All channel strips feature segmented level meters that display the playback or input monitoring level. The input monitoring level is displayed when you arm an audio track in preparation for recording.

Figure. Channel strips with level meters in different colors.

The colors of the level meter segments provide an at-a-glance overview of individual channel strip monitoring levels:

  • Amber and yellow: These signals are safe, and will not clip the channel strip output.
  • Red: These signals are considered “hot” levels, but the occasional peak is nothing to worry about unless the clip indicator is continually or regularly lit.

Customizing a Channel Strip’s Level Meter Scale

You can customize the level meter using two different scales.

Figure. Level meters displaying exponential scale and sectional dB-linear scale.
To change the level meter scale
  1. Open Display preferences by doing one of the following:

    • Choose Logic Express > Preferences > Display (or use the Open Display Preferences key command).

    • Click the Preferences button in the Arrange toolbar, then choose Display from the pop-up menu.

  2. Click the Mixer tab, then choose a value in the Scale pop-up menu.

    • Exponential: Provides higher display resolution in the upper range.
    • Sectional dB-linear: Provides the best possible display resolution across the entire level range.

Switching Between Channel Strip Volume Levels

You can use the following key commands to quickly switch between two different volume levels on a channel strip:

  • Toggle Level of Audio Channel Strips

  • Toggle Level of Auxiliary Channel Strips

  • Toggle Level of Output Channel Strips

  • Toggle Level of Input Channel Strips

  • Toggle Level of Bus Channel Strips

To switch between two volume levels
  1. Select an audio channel strip, for example.

  2. Set the Volume fader to the required level.

  3. Use the “Toggle Level of Audio Channel Strips” key command.

    Note that the channel strip’s Volume fader is all the way down.

  4. Set the Volume fader to an alternative level.

    The “Toggle Levels of Audio Channel Strips” key command now toggles between the two volume levels. It does so for all channel strips of the same type at once, allowing you to create two different mixes from one set of channel strips.