Flex Time and Flex Pitch

Flex changes the timing and tuning of recorded audio without cutting it up. Flex Time moves a hit and stretches the audio around it; Flex Pitch moves the notes a voice sings; Smart Tempo gives a performance played without a click a grid. All of it happens in the audio editor: choose an audio region and open the editor (⌘E).

Turn on Flex Time

There is no switch: choose the Flex tool in the tool picker at the top of the audio editor. The hits it can grab are marked on the waveform.

Flex works on an audio region that does not loop or play reversed. A region with Follow Tempo off, in a song whose tempo changes, cannot take flex either. Nor can a launcher clip open in the editor: it loops in its cell, so flex would not be heard. The editor says so under its header while the Flex tool or Flex Pitch is out; place the clip in the arrangement to flex it.

Move a hit with Flex Time

Drag a hit to where it should play. The waveform shows the result while you drag.

Drag from the upper half of the region: the hits either side stay where they are, and only the audio between them stretches.
Drag from the lower half: only that hit moves.

Let go. Each drag is one undo step.

The drag snaps to the arrangement's snap, never coarser than a sixteenth. Turn snap off to place a hit freely. Double-click a marker to remove it. To take every marker away, right-click the region and choose Reset Flex.

Follow Tempo and stretch modes

With Follow Tempo on in the inspector, an audio region stays on its beats when the tempo changes; off, it plays at its own speed (see Audio that follows the tempo in The arrangement). How it is stretched, for the tempo and for flex, is its Stretch Mode:

Polyphonic: chords, pads, full mixes, the pitch kept. The usual one.
Monophonic: one voice, such as vocals, bass or a lead line.
Slicing: drums. Every hit plays as recorded; gaps are left when slower.
Rhythmic: guitars and keys. Hits as played, gaps filled.
Speed (FX): like tape, faster is higher and slower is lower.
Tempophone (FX): a grainy, robotic flutter as the tempo moves.

Claude can do this for you: ask it to set a region's stretch mode, or to make it follow the tempo.

Quantize audio

To tighten a drum loop or a played part, right-click the region in the audio editor and choose Quantize Audio, then 1/4 Note, 1/8 Note, 1/16 Note or 1/32 Note. Every hit moves onto the grid, the audio between hits stretching, in one undo step.

On tracks in an edit group, the regions playing at the same time on the group's other tracks are quantized with it, so the microphones stay in phase (see Recording several tracks).

Claude can do this for you: ask it to quantize a region's audio to a grid, with a strength if you want the feel kept, or to reset its flex.

Align audio to a guide

To fit a double, a backing vocal or an ADR line to the timing of a guide (the lead vocal, the original take), as Cubase's AudioAlign and VocAlign do:

Choose the regions. Choose the guide too, on the track above, or choose only the regions to align and Nebula suggests the region playing with them longest on another track.
Choose Align Audio… from the region's right-click menu, in the arrangement or the audio editor, or Track ▸ Align Audio….
Check the Guide, then set:

Precision: Loose follows phrases, a marker on each hit and about every half second. Medium is the usual one. Tight follows syllables, a marker about every 80 ms.
Amount: how far each moment moves toward the guide. 100 % lands it on the guide; less keeps some of the original feel.
Max Shift: how far apart the two may be, from 50 ms to a second. Raise it for a line that was well off.
Align pitch too: each note is also tuned toward the guide's note, through Flex Pitch, by Pitch Amount. A double an octave below stays an octave below. Use it on single voices.

Click Align. It is one undo step for every region.

Nebula matches the two by how they sound: their loudness, their attacks and their tone, so a double sung softer or through another microphone still lines up. A hit that comes within 30 ms of a hit of the guide lands exactly on it.

The result is ordinary flex markers. Choose the Flex tool to see and move them, and Reset Flex to take them away. Flex Pitch shows any notes it tuned. With the Marquee set in the audio editor, only the range inside it is aligned, and the audio outside stays where it was. A region in an edit group takes its group's regions with it, as every flex edit does; the guide never moves.

Claude can do this for you: ask it to align the doubles to the lead, with an amount, a precision, or the pitch too.

Replace or double a drum

To play a recorded kick, snare or tom with another sound, as Logic's Drum Replacement/Doubling does:

Choose the drum's audio regions, on one track. A whole take of a kick mic is the usual choice.
Choose Drum Replacement… from the region's right-click menu, in the arrangement or the audio editor, or Track ▸ Drum Replacement….
Set:

Replacement or Doubling: Replacement mutes the original regions; Doubling keeps them playing under the new sound.
Drum: which drum it is, and so the note each hit plays (36 for a kick, 38 for a snare). Change the Note for a kit laid out its own way.
Sound: a built-in kit, Nebula Kick or Nebula Drums when they are installed, or Sample… for a one-shot of yours, which Nebula Sampler plays at its own pitch.
Sensitivity and Minimum Spacing: how many hits are found. Lower the sensitivity to leave out the other drums' bleed. The lines in the picture are the hits.
Timing Offset: moves every new hit up to 30 ms later or earlier against the original.

Click Replace (or Double).

A new drum track appears under the original, with a MIDI region where each audio region is. Each note sits on its hit's attack and is as loud as the hit was, against the loudest hit in all the regions, so a chorus played harder stays harder and ghost notes stay quiet. A sample's own attack is allowed for: a kick sample with a few milliseconds before its hit plays that much earlier, so the two hits land together. It is one undo step, the mute included.

Claude can do this for you: ask it to replace the kick with a sample, or to double the snare with a kit.

Flex Pitch: see the notes

Click FLEX PITCH in the audio editor's header. The waveform makes way for the notes the voice sings or plays, against a keyboard (Finding notes… while Nebula listens). Click it again for the waveform. Flex Pitch is for one voice: a vocal, a bass line, a lead.

Flex Pitch: change a note

To tune a vocal or a solo one note at a time:

Drag a note up or down with the Pointer or the Pencil to move it by semitones. Option-drag to move it by cents.
Click a note with the Scissors to cut it in two.
Click a note to select it. A bar of controls appears above the notes:
The minus and plus buttons move it down or up a semitone; FINE moves it by up to 50 cents either way.
DRIFT straightens the pitch wandering inside the note, from 0 to 100 %.
VIBRATO shrinks or deepens the vibrato, from 0 to 200 %.
GAIN turns the note up or down, from −30 to +12 dB.
FORMANT shifts the voice's character without changing the note.
Correct tunes the note to the song's scale; Join Next joins it with the note after it; Reset puts it back as it was sung.

Correct pitch for a whole region

In the Flex Pitch view, right-click the region and choose Correct Pitch to the scale shown, then 100%, 75% or 50%. Every note moves that far toward the nearest pitch of the scale. 100 % lands every note exactly; less keeps it natural. Reset Flex Pitch takes every note's change, cut and join away.

Claude can do this for you: ask it to correct the pitch of a vocal region, with a strength.

Create MIDI Track from Pitch

To turn a sung or played line into MIDI, choose the audio region, then Track ▸ Create MIDI Track from Pitch (also on the region's right-click menu). A new instrument track appears under it, with the notes where the region plays them and their loudness as velocity.

Claude can do this for you: ask it to turn an audio region's notes into MIDI.

Smart Tempo: give a free performance a grid

When a band or a drummer played without a click, Smart Tempo finds the beats and makes the song's grid follow them. Right-click the region in the audio editor and open Smart Tempo:

Detect Beats finds the beats and shows them on a strip along the foot of the region.
Adapt Song Tempo to Region rewrites the song's tempo so the bar lines land on the region's downbeats: a tempo change on every beat. The audio is not moved, and everything else keeps its moment in time.
Adapt Song Tempo, Parts Keep Their Bars does the same, but notes, regions and markers keep their bars.
Flex Region to Song Tempo leaves the tempo alone and flexes the region onto the grid, each beat a flex marker.
Clear Beats takes the beats away.

The Adapt and Flex commands find the beats first if you have not. Smart Tempo works on an audio region that does not loop, does not play reversed and is not a take folder.

Smart Tempo: correct the beats

Where Nebula heard a beat wrong, correct it on the strip at the foot of the region:

Drag a beat onto the hit it belongs on.
Double-click the strip to add a beat, or double-click a beat to delete it.
Right-click a beat for Make Downbeat (the first beat of a bar), Not a Downbeat or Delete Beat; right-click between beats for Add Beat Here.

After each correction, an adapted tempo or a flexed region follows the beats again.

Claude can do this for you: ask it to detect a region's beats, or to adapt the song's tempo to a region.

Spectral editing: see the sound

Click SPECTRUM in the audio editor's header, or choose View ▸ Spectrum, which opens the editor too (give it a key in the Key Commands window). Each region shows its sound by time (across) and frequency (up, from 20 Hz at the foot), quiet to loud from dark to bright. A cough, a click, a chair squeak or a phone shows as a shape of its own over the music. Click SPECTRUM again for the waveform. Flex Pitch and the spectrum take turns: turning one on turns the other off.

Spectral editing works on an audio region that plays forwards and does not loop, and not on a take folder. It works on a launcher clip open in the editor too: the edit is made in its cell, and the clip loops the edited sound.

Spectral editing: select a sound

Choose the selection's shape in the editor's left column: the rectangle, or the lasso.

With the rectangle, drag across the sound: its start and end in time, its lowest and highest frequency.
With the lasso, draw round it.
Drag past the top or the foot to take every frequency to that edge: a click or a cough is every frequency.
Click the spectrum to clear the selection.

Selecting is not an edit: nothing is changed until you choose what to do to it.

Spectral editing: turn down, erase or heal

With part of the spectrum selected, choose in the left column or on the right-click menu:

Apply Gain turns the selection up or down by the gain beside it, from −60 to +12 dB: to tame a whistle, a ringing note or a breath in its band.
Erase silences the selection.
Heal fills the selection from the sound either side of it in time, as if the noise had not been there: for a click, a cough or a squeak over a steady sound.

Keep a selection tight: everything inside it is changed, and nothing outside it is. The selection stays, so you can press again to go further. Each edit is one undo step.

The region's file is never changed. Nebula renders a new file with the edits in it and the region plays that, starting from the original each time, so edits never pile up on each other. The new file keeps the original's length and clock, so the region's trims, Flex and beats stay where they were, and the region can still be lengthened into the rest of its audio.

Spectral editing: take an edit back

Remove Last takes the region's last spectral edit out and renders the rest again. Revert All puts the region back on the audio it played before any spectral edit. Both are on the right-click menu too, and both are one undo step.

Varispeed

Varispeed plays the whole song faster or slower, for practising a part, recording at another speed, or a tape feel. It sits in the transport bar beside the tempo.

Type an amount in the field, or drag it up or right to raise it and down or left to lower it. It goes from -50% to +100%.
Click the mode under it to choose Varispeed (Speed and Pitch), where faster is higher as on tape; Speed Only (Pitch Kept), where the tempo changes and audio is stretched to keep its pitch; or Off.
Show As in the same menu shows the amount as Percent, Semitones & Cents, Tuning (Hz) or Resulting Tempo. Type in whichever unit is shown.
Reset to 0 puts it back to normal speed.

A bounce is what you hear: it includes Varispeed, in either mode.