This section covers the controls for recording, playback, fade, count-in, metronome, and undo operations.
Transport and Function parameters
Record button: Starts or stops recording. Click the Record button once to start recording to the tape loop—a virtual tape loop, not an actual one. Click a second time to set the length and start overdubbing. During overdubbing, the first recorded take plays back while you record subsequent takes. Subsequent clicks toggle recording off or on, while the tape loop keeps playing.
Play/Stop button: Starts playback at the position set by the Play From and Snap To parameters. If Loopback is playing or recording, stops immediately (without waiting to reach the Snap To value). If Loopback is recording and has no established length, it sets the length and just continues to play back with no overdubbing. See Loopback Sync, Snap To, and Play From parameters.
Reverse button: Reverses the contents of the tape loop, so the sound plays back in reverse. You can activate Reverse when Loopback is either playing or stopped.
Fade Out button: Gradually lowers the volume level of the tape loop over the time specified in the Fade Time field. The Fade Out button remains highlighted until the fade-out has finished and playback stops.
The fade-out affects only previously recorded material. You can start recording during a fade-out, and the new material is recorded and plays at full level. When you record new material during a fade-out, Loopback does not stop when the fade-out has finished, but continues playing the newly recorded material.
If the tape loop length has been set, pressing the Fade Out button (or activating a screen control mapped to it) while Loopback is playing clears the buffer, but does not reset the loop length. Pressing the Fade Out button while Loopback is stopped clears the buffer. If the loop length was undefined when Loopback started playing, it also resets the loop length.
Count-in button: Enables a one-bar count-in, using the concert time signature.
Metronome button: Turns the MainStage metronome on or off.
Undo button: When pressed during playback or when stopped, removes the most recently recorded take from the tape loop. Pressing Undo during the first beat of a new take removes the previously recorded take.