Enable tracks for recording in Logic Pro for iPad
You enable a track for recording by tapping the track’s Record Enable button 
in the track header, or by selecting a single track, making it the focused track. When you enable a track by tapping its Record Enable button, the button blinks red. When you give a track focus, the letter “R” in its Record Enable button turns red.
When you start recording (by tapping the Record button 
in the control bar), Record Enable buttons of enabled tracks turn solid red; they return to their previous state when recording ends.
You can enable multiple tracks as long as each track has a unique input (chosen in the Input slot in the Mixer). Multiple tracks that use the same input cannot be simultaneously record enabled.
For information about recording to multiple audio tracks, see Record to multiple audio tracks. For information about recording to multiple software instrument tracks, see Record to multiple software instrument tracks.
Enable a track for recording
In Logic Pro, show the track controls (if they are not already visible).
Do one of the following:
Tap the Record Enable button
in the track header.When no track is record enabled, select a single track.
If the Record Enable button does not appear in the track headers, customize the track headers so that it is visible.
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