Some sections, or even entire songs, do not get recorded to a click track, thus having tempo changes. Tempo Mapping is the process of automating those tempo changes.
The goal of tempo mapping is to sync every beat in a measure the same way these are synced in a song that was fully recorded to a click track.
Use a stem where the beats can easily be seen throughout the song. Usually PIANO, DRUMS, or LOOP can be helpful.
Steps to Tempo Map a Song
Press the A key on the keyboard. This activates the Automation Mode in Ableton.
Using the mouse pointer, highlight a section that you want to change the tempo of within the automation lane shown in the MASTER output track. (This can be 1 beat, 2, beats, 1 bar, 2 bars, etc. See first image below.)
In the MASTER track, set the maximum tempo of the song to the previously established average tempo and set the minimum tempo to a lower tempo than the average. (For the sample song below this range is set to 126 to 130)
Click and drag the tempo of that section up or down. You can highlight just above or below the orange line to adjust that section.
If you hold the SHIFT key, you can be more precise with your tempo changes.
Do NOT use gradual tempo changes by creating ramps up/down in the tempo grid, as this causes errors in Playback.
Establish an average BPM of the song.
For the example seen below, the average bpm is 130. All stems are perfectly synced at measure one but go out of sync by measure 7 and back into sync around measure 10.
Drag the DRUMS and the PIANO tracks and place them right beneath under the ORIGINAL SONG track to easily visualize the beats in the measures.
Try to always use whole numbers for the minimum and maximum tempos. (Only go to the tenth if you have to.)
Find the first beat in the song where the tempo begins to fluctuate and use the described Tempo Mapping steps above to sync the next beat or beats to the grid or click. (TIP: A black line should appear at the end of the highlighted section, which can be used to help line up the tempo map with the stems.)
Continue to draw in tempo changes as needed.
As shown in the 4th image below, the maximum and minimum song tempo range might need to be adjusted depending on how the changes tempo changes.
Seen on the right is a highlighted section which can be dragged up or down to adjust the tempo of the song for that section.
Song is out of sync at measure 7 and the tempo range is set to 126 to 130.
Tempo change is added in and the beats now line up at measure 7.
Properly tempo mapped section. Notice how the transients always align with the beats of each measure.
Correct vs. Incorrect Tempo Mapping
NOTE: NEVER have the COUNT OFF tempo be different from the first part of measure 3 of the song.
Double check that tempo mapping looks like the first image below and not like the second image below.
NEVER use ramps/slopes to do tempo mapping, no matter what. (See second image for an example of a ramp/slope.
Correctly tempo mapped section.
Incorrectly tempo mapped section.
Tempo Mapping the Ending of a Song
Some songs might have a steady tempo throughout, but in the last measure will begin to slow down as it goes into the ENDING. These songs will only need tempo mapping on that last measure but the same process will be used.
The last beat of the song should be perfectly aligned with the ENDING locator.
TIP: Try to use tempo changes to do so unless there is a very clear additional beat, in which case you can try a time signature change. Most of the time, a tempo change will be enough.
The original BPM must be set back to the beginning tempo at the ENDING locator.
There should not be any tempo changes after the ENDING locator.
The BPM for most of the song above is 74 bpm and it slows down from measure 78 to the ENDING at measure 79. The last measure of the song is tempo mapped and the BPM is set back 74 bpm at measure 79.
NOTE: Just as the ENDING section is not tempo mapped, the COUNT OFF section should never be tempo mapped.
For information on adding tempo changes to cloud songs for Playback, see
HOW TO | Tempo Changes in Cloud Songs