# Transport
## Tempo
Drag to set the current tempo according to the position where your timeline is. (For multi-tempo projects, adjusted tempo will only be applied for the section where your timeline is in.)
Double click to type in the exact number of tempo.
ACE Studio supports a tempo range of 1-360 bpm.
{% hint style="info" %}
If your project involves tempo changes, please refer to [Tempo & Signature Change](/project/arrangement-in-canvas/tempo-and-signature-change.md).
{% endhint %}
## Time Signature
Drag to set the current time signature according to the position where your timeline is. (For multi-signature projects, adjusted signature will only be applied for the section where your timeline is in.)
Double click to type in the exact number of signature.
{% hint style="info" %}
If your project involves time signature changes, please refer to [Tempo & Signature Change](/project/arrangement-in-canvas/tempo-and-signature-change.md).
{% endhint %}
## Playback/Record Controls
#### Back to start
Click to jump the timeline back to the beginning of the project.
* Shortcut key Enter
#### Play/stop
Click to start or stop the playback.
* Shortcut key Space
The playback will always start from the marker-line. If you stop the playback and play again, the playback will still start from the the same start position as last time, unless you relocate the marker-line.
To continue the playback from where you stopped, use shortcut Shift + Space.
#### Record
Click to start/end recording.
* Shortcut key R
If the playback is not started, start recording will also start the playback. You can also start recording during the playback.
For more detailed information about Record, please refer to [Record](/project/arrangement-in-canvas/record.md).
## Metronome
Click to turn on/off the metronome.
## Loop
Click to toggle loop mode on or off.
### Loop Brace
When loop mode is enabled, loop brace will appear on the time ruler. You can adjust the length of the loop brace by dragging its edges or reposition it by dragging directly. You can also click on the loop brace to turn on/off the loop mode.
After selecting a region, use the shortcut Ctrl/⌘Command+L to turn the selected area into a loop brace. Press the shortcut again to exit loop mode.
When exporting audio, select Export Range as Loop to export the audio within the Loop Brace range. For more details, please refer to [Export Files](/project/file-management/export-files.md).
## Auto Scrolling
Click this trigger to toggle auto-scrolling on or off. During playback, the Arrangement View and Clip View will automatically scroll when the timeline reaches the end of the visible area.
During playback, auto-scrolling will be temporarily disabled if you manually scroll the view until next playback. You can turn it on by clicking.
You can set scrolling animation in Preferences. For more details, please refer to [Preferences](/account-and-settings/preferences.md).
## Timecode
This shows the time position of time-line.
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