Tempo

The Big Concept

This is the thing you need to understand before anything else in this chapter will make sense.

MIDI is locked to beats. Audio is locked to clock time. When the tempo changes, these two types of data respond differently.

Speed up the project from 100 BPM to 120 BPM. A MIDI region that starts at bar 5, beat 1 still starts at bar 5, beat 1 — but bar 5 now arrives sooner in real-world seconds. The MIDI plays faster because the beats are closer together. This is automatic. You do not have to do anything.

An audio region, by default, is also pinned to a bar position. But the audio itself does not change speed — it is a recording of a fixed duration. Speed up the project and the audio still takes the same number of seconds to play. The bar lines move, but the audio does not stretch. The result: the audio drifts off the grid.

This mismatch is the source of most tempo-related confusion. MIDI flexes with tempo automatically. Audio does not — unless you tell it to (with Flex Time, Follow Tempo, or by importing it with Smart Tempo in Keep mode).

The practical implication: every time you change the tempo of a project that contains both MIDI and audio, you need to think about what happens to the audio. Does it need to stretch? Does it need to stay put? The answer depends on the situation, and Logic gives you tools for each one.

Detect Tempo

When you have a recording that was performed without a click — a live band take, a vocal freestyle, a guitar demo — Logic can analyze the audio and figure out where the beats fall.

Edit > Tempo > Detect Tempo of Selected Region analyzes the selected audio and creates a tempo map. The Tempo track fills with values that follow the performer’s natural timing, beat by beat.

The detection dialog gives you options:

• Apply Region Tempo to Project writes a detailed tempo map with beat-by-beat variation. Each beat gets its own tempo value. This is what you want when the performance has intentional tempo fluctuations — a rubato intro, a band that speeds up in the chorus — and you want everything you add afterward to breathe with that performance.
• Use an Average Tempo calculates a single BPM value and sets the project to that. Simpler and cleaner for most uses. If the performance is relatively steady, this gets you close enough.

A practical note: tempo detection works best when the audio has clear rhythmic content. A strummed guitar, a drum performance, a rhythmic piano part — these give the algorithm transients to latch onto. A sustained pad or a legato vocal line may not have enough rhythmic information for accurate detection.

Adapt Tempo

Smart Tempo gives you three modes, set in the LCD or under File > Project Settings > Smart Tempo:

Keep is the default and where most beat-building lives. You set a tempo, and anything you bring in gets conformed to fit.

Adapt flips that relationship. You are telling Logic that the imported audio is the authority, and the project tempo should defer to it. This is the mode for when a band recording or a vocal take is the foundation and everything else needs to follow its natural timing.

Auto tries to figure out which approach makes sense. If you have existing tracks, it assumes Keep. If the project is empty, it adapts. Convenient, but it can make surprising decisions. When tempo matters, pick Keep or Adapt deliberately.

Free Tempo Recording

This is the workflow for capturing an idea when you have no tempo in mind. You are not playing to a click, not counting in — just playing.

Enable Free Tempo Recording by customizing the Control Bar (right-click the Control Bar, choose Customize, and add the Free Tempo Recording button). Click it and Logic starts recording immediately — no metronome, no count-in, no cycle. Play your idea. When you stop, Logic presents a dialog.

The options:

• Apply Region Tempo to Project — Logic writes a detailed beat-by-beat tempo map that follows your performance.
• Apply Average Region Tempo to Project — Logic calculates a single average BPM. This is what you want most of the time. You played at roughly 92 BPM with human variation, and Logic rounds it to a steady tempo you can build on.
• Time-stretch to existing tempo — Logic conforms your recording to whatever tempo the project was already set to.
• Don’t do anything — Logic keeps the recording but leaves the tempo alone.

Free Tempo Recording captures MIDI and audio. For MIDI specifically, there is a companion tool: Capture Last Take as Recording grabs whatever you were just playing even if you were not officially recording. Logic is always listening to incoming MIDI. If you were noodling on a keyboard and stumbled into something good, Capture lets you keep it after the fact. Between Free Tempo Recording and Capture, you have covered the two main “I was not ready but that was good” scenarios.

Set Tempo by Region Length and Locators

This is a more surgical approach. You have a recorded passage and you know it is supposed to be a specific number of bars — say, eight bars. But you do not know the exact BPM.

The procedure:

1. Cut the recording to a clean boundary.
2. Drag it to the beginning of a bar.
3. Set locators around the number of bars you want it to fill (bar 1 to bar 9 for eight bars).
4. Edit > Tempo > Adjust Tempo using Region Length and Locators.

Logic calculates the tempo needed to make the region fit exactly within those bar boundaries. The audio does not change — no stretching, no warping. Logic adjusts the project tempo so the grid aligns with what you recorded.

The result is sometimes an irregular number like 83.917 BPM. You can round it if you prefer a clean number, but the region will drift slightly over time at the rounded value. If you keep the odd number, the loop cycles perfectly. Your call depends on whether the exact tempo matters for collaboration or sharing.

Tempo Changes and Curves

The Tempo track (visible in the Global Tracks, toggled with Show/Hide Global Tracks, default G) lets you write tempo changes directly into the project.

• Click in the Tempo track to create tempo nodes
• Drag nodes up or down to set the tempo at that point
• Drag between nodes to create smooth curves

An

Tempo changes affect everything in the project at that point in the timeline. MIDI regions play faster or slower accordingly — that is automatic. Audio regions do not stretch with tempo changes unless they have Follow Tempo enabled or Flex is active. Regions that are SMPTE-locked ignore tempo changes entirely. Knowing which regions are affected by a tempo change is part of managing a project with variable tempo.

SMPTE Lock

Every region in Logic lives in one of two time systems by default. Most regions are attached to musical time — bar 5, beat 1. Change the tempo, and that position now falls at a different point in clock time. The region shifts.

SMPTE Lock switches a region to absolute time — a fixed position measured in hours, minutes, seconds, and frames. Select a region, choose Region > SMPTE Lock (or right-click > SMPTE Lock Position), and a small lock icon appears. Now if you add a tempo change before it, the region stays at its clock-time position while other regions shift with the tempo.

Two situations where SMPTE Lock matters most:

Scoring to video. A sound effect needs to land at a specific frame — the exact moment a door slams. If you later adjust the tempo in a preceding section, you need that sound to stay put. SMPTE Lock keeps it anchored to clock time.

Protecting audio during tempo experiments. If you are adjusting the tempo of a section and you have audio regions that are already aligned correctly, SMPTE Lock prevents them from drifting while you experiment.

To remove the lock, select the region and toggle SMPTE Lock off. The lock icon disappears and the region returns to musical time.

Follow Tempo

Audio regions have a Follow Tempo option, visible in the Inspector when a region is selected. When enabled, the audio stretches or compresses in real time to match tempo changes in the project.

This is how Apple Loops work — they follow tempo automatically because that flag is already set. For your own recordings, you can enable Follow Tempo manually. The quality of the stretching depends on which Flex mode is active (covered in Chapter 13). It works well for rhythmic material — drum loops, guitar strumming, rhythmic synths. It gets increasingly strange on sustained sounds or complex polyphonic content.

Enable Follow Tempo when you want an audio region to stay locked to the grid through tempo changes. Leave it off when the audio should keep its original timing and sit where it sits.

Varispeed

Varispeed changes the playback speed of the entire project. It is a different approach from tempo changes — instead of adjusting the grid, you are adjusting the playback engine, like speeding up or slowing down a tape machine.

Enable Varispeed by adding it to the Control Bar (right-click the Control Bar > Customize). You get a speed control and a mode selector:

• Speed Only — Changes playback speed without changing pitch. The project plays faster or slower, but everything stays in tune.
• Speed and Pitch — Changes both, like speeding up a turntable. Faster playback = higher pitch.
• Varispeed (Percentage) — Set the speed as a percentage of normal (100% = normal, 50% = half speed).
• Varispeed (Resulting Tempo) — Set the desired tempo and Varispeed calculates the speed change.

Varispeed is useful for practicing: slow a complex passage down to learn it, then bring it back up to speed. It is also a creative tool — the Speed and Pitch mode produces that classic tape-speed effect where everything pitches up or down together.

Varispeed affects playback only. It does not change the project data. Turn it off and everything returns to normal.

A Map of Tempo Tools

What to Practice

• Change the project tempo and watch what happens to MIDI regions vs. audio regions. MIDI adapts automatically. Audio does not. This single observation is the foundation of everything else in this chapter.
• Record or import an audio file with clear rhythm. Run Detect Tempo (Edit > Tempo > Detect Tempo of Selected Region) and choose the average tempo option. Compare the result to what you would estimate by ear.
• Try Free Tempo Recording. Add the button to your Control Bar, record a MIDI performance with no click, and choose “Apply Average Region Tempo to Project.” Check the LCD for the calculated tempo. Turn on Cycle and see if it loops cleanly.
• Take a freely recorded passage. Cut it to a clean boundary, drag it to bar 1, set locators around the number of bars it should fill, and run Adjust Tempo using Region Length and Locators. Verify the loop cycles at the new tempo.
• Draw a tempo change in the Tempo track — a gradual accelerando across four bars. Watch how MIDI regions on other tracks speed up through that section. Then enable Follow Tempo on an audio region and watch it stretch. Disable Follow Tempo and watch it drift off the grid.
• Try the accelerando drum roll exercise described above. Create the tempo ramp, SMPTE Lock your audio, restore the tempo, and listen to the result.
• Enable Varispeed and slow the project to 50%. Practice a complex passage at half speed. Then bring Varispeed back to 100% and play along at full tempo.
• Turn on the secondary ruler (View > Secondary Ruler) and set it to clock time. Change the project tempo and watch the clock-time positions shift while the bar/beat positions stay the same. This makes the musical time vs. clock time distinction visible.

Commands in This Chapter