Latency and the Sound Manager

When using the Mac’s built-in audio to record (via the system software’s Sound Manager), you may periodically find that your audio is slightly offset from where you thought you began recording. This is called latency. (Dedicated audio cards you add to your Mac, like the Sonorus STUDI/O,. and the Korg 1212I/O, don’t display this problem.)

If you notice some offset audio, you’ll need to make subtle adjustments to the start times of new audio tracks. These minor adjustments are easily done with the Delete Time (Shift-Command-d) and Insert Time (shift-Command-i) selections in the Edit menu.

Here’s some more detail about what to do if you notice any timing problems with your new audio track and the previous tracks:

  1. In the Tracks window, double-click the name of your audio track.

The Graphic Editor window appears, displaying your new audio track.

  1. Use the scroll bar at the bottom of the window to scroll to a region of blank space that comes before the audio waveform.

  2. Use the Select tool (the pointer) in the Graphic Editor to click and drag a small amount of blank space.

  3. From the Edit menu, choose DeleteTime or Insert Time to reconcile the start times. Experiment until the timing sounds acceptable.

There will be many occasions like the one above when it will be helpful to Zoom all the way in to the Sample level on a waveform in the Graphic Editor in order to make precise edits. Let’s do it now to get a feel for it:

  1. Select a small section of your recorded audio with the Select tool.

  2. Click the Magnifying Glass Icon with the plus sign or press Command- = to Zoom in on the waveform. You will notice the wave getting more and more detailed as you do.

  3. To Zoom back out again, click the Magnifying Glass with the minus sign or press Command- - to Zoom back out to your desired level.

If you select data in a MIDI track instead of an audio track, Metro will always let you zoom in and out, but won’t burrow all the way down to the audio sample level; this actually saves some time, since Metro doesn’t have to calculate the wave’s image each time you zoom in to look at MIDI.

Changing Audio Volume

Latency and the Sound Manager