Corrigit Documentation

1. Introduction

Someone recorded a demo on their phone. No click, tempo wandering the way real playing does. To give a drummer something to play to, you have normally had two ugly options: re-record the whole song to a metronome, or sit in a DAW hand-placing tempo changes beat by beat until it lines up.

Corrigit removes that step. Point it at the take you already have, mark which parts should stay loose and which should lock to a steady beat, and it writes out a click-locked reference the drummer plays straight to. No re-recording, no beat-by-beat tempo editing, and you do not have to open a DAW at all.

Who touches what

You do the work here. That is the whole job.
The singer never opens this app. They recorded the demo. They are done.
The drummer never opens it either. They get the finished files and play.

Everything stays on your machine

Corrigit decodes, analyses and renders locally. No audio is uploaded anywhere. The only thing that ever leaves the machine is a licence activation, and that carries nothing about your music.

Corrigit with a demo loaded — Figure 1-1. A take just imported. One Follow region covers the whole file, the detected beat grid is drawn over the waveform, and the controls underneath act on whichever region is selected.

2. Installing and First Launch

Installing

Run the installer. It installs per-user with no administrator rights to your local application folder, adds a CORRIGIT Start-menu entry, and offers a desktop shortcut. Accept the licence to proceed.

Windows will warn on an unsigned build with a blue "Windows protected your PC" box. Click More info, then Run anyway. A SHA-256 checksum is published next to the download if you want to verify what you got before running it.

What you need

Windows 10 or 11, 64-bit. Nothing else — no DAW, no plug-in host, no audio interface beyond whatever you already listen through.

What it will open

WAV, AIFF and FLAC are read directly. .m4a and AAC — which is what an iPhone voice memo actually is — are read through Windows' own media decoder. In practice: hand it the file off the phone and it works.

SOUNDTOUCH.DLL sits next to CORRIGIT.EXE and does the time-stretching. If you ever copy the program somewhere by hand, copy both. On its own the executable will not run.

3. Quick Start: Your First Export

Five minutes, start to finish. The rest of this manual is the detail behind these six steps.

IMPORT (top-left) and pick your take. Corrigit decodes it and finds the beat. You get a waveform with a faint line on every detected beat.
Carve a region. Double-click the waveform to split it where a section changes. Click the part that should sit on a steady beat — a verse, a chorus — and press LOCK. Leave loose, free-time parts on FOLLOW.
Place the "1". On a Lock region the "1" is its left border — drag that boundary onto the true downbeat by ear. On a Follow region, drag the little 1 pennant at the top onto the downbeat.
Set the BPM on each Lock region, or leave AUTO on and it uses that section's own detected tempo. AUTO is usually right.
PREVIEW. You hear the click in one ear and the take in the other. Listen right through — the one bar you skip is the one that is wrong.
EXPORT. Pick a folder. Six files land in it (section 10).

Do it in that order. Regions first, then the "1", then listen, then export.

4. Follow and Lock

A click is the steady tick a drummer plays to. The trouble with a loose demo is that the tempo moves, so a fixed tick would drift out of time with the music and be worse than useless.

So you split the song into regions and pick a mode for each. There are two, and that is the whole idea of the app:

Mode	The click	Your audio	Use it for
FOLLOW	Follows the playing wherever the tempo wanders.	Untouched. Not stretched, not processed, exactly as played.	Intros, rubato, free sections — anywhere the feel matters more than the grid.
LOCK	Holds a steady BPM you choose.	Gently time-stretched to sit on that beat.	Verses, choruses — anything that is supposed to be metronomic.

Most songs use both. Do not overthink which is which; your ears already know. Where two regions meet, Corrigit crossfades between them so the join does not click.

Trying to Lock a free-time intro just fights the music. If a section was played loose on purpose, leave it on Follow — the click will track it, and that is the better answer.

A song split into Follow, Lock and Follow regions — Figure 4-1. Three regions: a Follow intro, a Lock section at 70 BPM (the warmer band, labelled LOCK 70), and a Follow tail. The selected region is the one the controls underneath act on.

5. The Timeline

The tall grey shape is your audio. Louder is taller. That is all it is.

The faint vertical lines are the beat grid — where Corrigit reckons each beat lands. Brighter lines every few beats are bar lines, the top of each measure.

Getting around

Control	What it does
+ / −	Zoom in and out.
FIT	Zoom back out to the whole song.
Mouse wheel	Zoom toward the cursor. Faster than the buttons.
BAR SNAP	When on, dragging a region boundary snaps it to the nearest detected beat. Turn it off to land between beats — which you will want when placing a Lock region's downbeat by ear.

Get in close before you start fussing with alignment. You cannot line up what you cannot see.

Corrigit does not play your file back on the timeline — there is no moving playhead. Hearing your work is what PREVIEW is for (section 10).

6. Regions

A region is a stretch of song running one mode. A fresh import is one big Follow region covering everything, and you carve it up from there.

Gesture	Result
Double-click the waveform	Splits the region in two right there.
Drag a boundary	Moves the line between two regions.
Double-click a boundary	Removes it — the two regions merge back into one.
Click a region	Selects it.
FOLLOW / LOCK	Sets the selected region's mode.

Everything in the controls row acts on whatever is selected. If you are changing a setting and nothing is happening, that is the first thing to check.

BPM on a Lock region

With a Lock region selected, either type a number into BPM, or leave AUTO lit and Corrigit uses that section's own detected median tempo. Auto is usually right. Type a number when you actually know the tempo and Auto has it wrong.

7. Placing the "1"

The detected grid is a starting point, not gospel. Real playing is sloppy, so you will be nudging it. That is normal — that is the job.

What you reach for depends on whether the region is Follow or Lock, because the "1" means two different things in the two modes. Get this and you have got the whole app.

On a Follow region — the "1" flag

Grab the little 1 pennant at the top of the region and drag it onto your downbeat — the "one" you would count out loud. It snaps to the nearest beat and slides that region's grid so the beat lands where you dropped it, pickups and lead-ins included. Each Follow region keeps its own downbeat.

Your other Follow tools, in the order you reach for them:

Tool	When
Ctrl + drag	Slips the whole region's grid earlier or later so the ticks line up against the peaks by eye. A readout shows how far you have moved it.
x2 / /2	The click is ticking twice as fast, or half as fast, as you feel it. Very common on the first pass. Do not panic, just halve it.
FLIP	The click is landing on the off-beats — the "and", or the backbeat — instead of the beat. Shoves it over half a beat.
BAR 1	Walks which beat counts as "one" forward by one per press. Another way to fix a downbeat sitting a beat off.

On a Lock region — the "1" is the left border

A Lock region's "1" is not a pennant you drag around inside it. It is the region's left edge. That edge is the downbeat: the steady grid is born there and marches forward at the BPM you set.

So you place the "1" by dragging the region's left boundary onto the true downbeat, by ear. Turn BAR SNAP off first if you need to land between detected beats, which you often will. Everything to the right of that border conforms to it automatically.

Because the border is the "1", the Follow fiddly-bits do not apply on a Lock region, and the app greys them out so they cannot mislead you: no draggable flag, no Ctrl-slip, no x2 or /2, no FLIP, no BAR 1. On Lock you have exactly two things to set, and that is the point — where the left border sits and the BPM. Set those two and you are done.

Rule of Thump. On FOLLOW, place the "one" with the 1 flag and fine-tune with Ctrl+drag. On LOCK, place the "one" by dragging the left border and set the BPM. Only touch x2 / /2 or FLIP if the whole feel is fighting you. Nine times out of ten it is the "one" or the tick rate — not some deep problem. Check those first before you go hunting.

8. Time Signature

The small 4/4 box at the bottom-left of the timeline sets how many beats are in a bar. That decides where the bar lines are drawn and which ticks get the accented downbeat sound.

Double-click it and type a number — anything from 2 to 12. A bare number is what it wants; if you type something like 3/4 it takes the 3 and ignores the rest.

BAR 1 next to it moves which beat counts as the top of the bar, one step per press. Use it when the bar lines are the right distance apart but landing in the wrong place.

The meter is one setting for the whole song. If a piece genuinely changes time signature partway through, set it to whichever the bulk of the song is in — the click still lands on every beat either way, only the accents and bar lines follow the meter.

9. The Click

CLICK picks the sound and the slider next to it sets how loud.

Sound	Character
Woodblock	Dry and woody. Cuts through a dense mix without being shrill. The default, and the right answer most of the time.
Beep	A clean tone. Easier to hear against very percussive material where a woodblock can get lost among the drums.

The downbeat — the "1" of each bar — gets a higher-pitched tick, so you can hear the top of the bar go by rather than having to count it. That is deliberate. Leave it on.

Set the level against the program, not on its own. The drummer needs to hear both, and the click should sit just proud of the music rather than drowning it.

10. Preview and Export

Preview

PREVIEW renders the whole thing and plays it back — click in one ear, program in the other — so you check it before you export, not after. The button turns into STOP while it plays.

Listen to the whole take. The one bar you do not check is the one that is wrong.

Export

EXPORT asks for a folder and writes six files into it:

File	What it is	Who it is for
click_only.wav	The click alone, mono.	A drummer who wants to drop it into their own rig.
panned.wav	Stereo: click hard left, program hard right.	The zero-setup path. Plug into anything with two channels — one ear gets the click, one ear gets the tune. No software, no fuss. This is the file that removes the DAW requirement.
program.wav	Your take after Corrigit stretched the Lock sections onto the grid, with the click stripped back off.	Someone adding their own click or a fresh drum take. Same performance, now actually in time.
original.ext	A byte-for-byte copy of what you imported.	Reference and archive. Never processed, never overwritten — it is there so you always have the real thing to go back to.
tempo.csv	The tempo map — see section 11.	DAW users. If you do not use a DAW, ignore both.
tempo.mid	The tempo map — see section 11.	DAW users. If you do not use a DAW, ignore both.

The exported program is level-matched automatically, so a quiet phone demo does not come back whisper-quiet. Your original copy is never touched by that.

11. Sending the Tempo Map to a DAW

Already work in a DAW? Export also drops your tempo map — the grid you see on screen, corrected, lined up against the raw take — so your DAW's own bars and beats fall where the music actually does. No hand-drawing tempo changes.

Your DAW	What to do
Logic, Pro Tools, Cubase, Studio One	Bring tempo.mid in as tempo — "import tempo", or just drag it in. Your session tempo then follows the performance. There is nothing else in the file, just the map.
Reaper	Run the included script, integrations/reaper/corrigit_tempo_import.lua, to pull the map in as tempo markers. Or import tempo.mid like everyone else. Your call.
Anything scriptable	tempo.csv is the same map as plain text — beat number, time, BPM, bar, and whether it is a downbeat.
GarageBand	One straight answer: it will not take an outside tempo map. It is stubborn that way. Use the click and program files instead — they do the job without needing a tempo map at all.

12. Saving Projects

SAVE writes a .corrigit project — your regions, modes, BPMs, meter and click settings. OPEN loads it back.

One catch: your source audio has to still be sitting where it was when you saved. Move it, rename it or delete it and the project cannot find it. Keep the take and the project file together and you will never hit this.

The project stores a reference to the audio, not the audio itself, so the files stay small and you are never carrying a second copy of the take around.

13. Controls Reference

Top row

Control	What it does
IMPORT	Load an audio file. Decodes it and finds the beat.
SAVE	Write a .corrigit project.
OPEN	Load a saved project.
PREVIEW	Render and play back. Becomes STOP while playing.
EXPORT	Render and write the six files to a folder.

Timeline tools

Control	Range	What it does
4/4 box	2 – 12	Beats per bar. Double-click and type.
BAR 1	—	Moves which beat is the top of the bar, one step per press.
BAR SNAP	on / off	Snap boundary drags to the nearest detected beat. On by default.
− / FIT / +	—	Zoom out, fit the whole song, zoom in.

Region controls

Control	Range	What it does	Modes
FOLLOW	—	Click tracks the drift; audio untouched.	both
LOCK	—	Click holds a steady BPM; audio stretched to it.	both
BPM	typed	The steady tempo for a Lock region.	Lock
AUTO	on / off	Use the region's own detected tempo instead of a typed BPM.	Lock
x2 / /2	—	Double or halve the tick rate.	Follow
FLIP	—	Shift the click half a beat.	Follow
CLICK	Woodblock / Beep	The click sound.	global
Level	slider	How loud the click sits against the program.	global

Gestures

Gesture	What it does
Click a region	Select it.
Double-click a region	Split it at the cursor.
Drag a boundary	Move it.
Double-click a boundary	Remove it; the regions merge.
Drag the 1 flag	Set that region's downbeat. Follow only.
Ctrl + drag in a region	Slip its grid earlier or later. Follow only.
Mouse wheel	Zoom toward the cursor.

Header

Control	What it does
DK / LT	Switches between the dark and parchment themes.
?	Opens the in-app quick reference.
LICENSE	Opens the activation panel (section 14).

Light theme — Figure 13-1. The parchment theme. The DK/LT button in the header switches between them.

14. Licensing

Corrigit runs for 3 days from first launch without a licence. The footer shows how many days remain. The trial is fully featured — nothing is held back, no watermark, no export limit — and it works offline.

Activating

Click LICENSE in the header.
Enter the email address your licence was issued to, and your serial.
Press ACTIVATE.

The footer changes to LICENSED. You do this once per computer. Activation needs an internet connection; nothing else does.

The activation panel — Figure 14-1. The LICENSE panel. Email and serial go in, ACTIVATE confirms, and DEACTIVATE releases the seat again.

Moving to another computer

One licence covers three machines. To free a seat, open the LICENSE panel on the machine you have finished with and press DEACTIVATE. The seat is available immediately and you can activate elsewhere.

Deactivate before you wipe, sell or retire a computer. Recovering a seat from a machine you no longer have means going through support.

If the trial expires

The app locks: the timeline and controls are hidden and nothing renders. Your projects and audio are untouched — activate and everything is exactly where you left it.

Privacy

Activation sends only what is needed to issue your licence. No audio, no projects and nothing about your music ever leaves your machine.

15. Troubleshooting

Symptom	What to do
The click feels wrong and you cannot say why	It is almost always one of two things: the wrong beat is "1", or the tick rate is doubled or halved. Fix the "1" first (the flag on Follow, the left border on Lock), then try x2 / /2. You will be right most of the time, and you will fix it in ten seconds instead of ten minutes.
The click is on the off-beats	FLIP, on a Follow region. One button, half a beat.
Nothing happens when I change a setting	Check which region is selected. Everything in the controls row acts on the selection only.
The Follow tools are greyed out	You have a Lock region selected. On Lock there are only two things to set: where the left border sits, and the BPM. That is by design.
I cannot get the Lock boundary exactly on the downbeat	Turn BAR SNAP off. It is snapping you to the nearest detected beat, and the true downbeat often sits between them.
A Lock section sounds warbly or smeared	The BPM you set is a long way from what was actually played, so the stretch is working too hard. Turn AUTO on to see what the section really is, or split it into two Lock regions if the tempo genuinely changed.
A free-time section sounds worse, not better	It is on Lock. Put it back on Follow — the click will track it and the audio will be left alone.
My project will not open	The source audio has moved, been renamed or been deleted. Put it back where it was.
The import failed	Check the format (section 2). A file that plays elsewhere but not here is worth reporting.
The app is locked	The 3-day trial has ended. Activate in the LICENSE panel.

16. Specifications

Product	Corrigit
Version	1.0.0
Type	Desktop application. No DAW or plug-in host required.
System	Windows 10 or 11, 64-bit
Install	Per-user, no administrator rights
Reads	WAV, AIFF, FLAC natively; .m4a / AAC through Windows' media decoder
Writes	Six files per export — click only, click + program panned, conformed program, untouched original, tempo.csv, tempo.mid
Region modes	Follow (audio untouched) and Lock (audio time-stretched to a fixed BPM)
Time signature	2 to 12 beats per bar, one setting per song
Projects	.corrigit — regions, meter and click settings, referencing the source audio in place
Network	Activation only. Audio is never uploaded.
Trial	3 days, fully featured
Seats	3 computers per licence

17. Glossary

Bar line	The brighter grid line at the top of each measure.
Beat grid	The faint vertical lines showing where Corrigit reckons each beat lands.
BPM	Beats per minute. How fast a steady click ticks.
Click	The steady tick a drummer plays to.
Conformed	Audio after the Lock sections have been stretched onto the grid — the same performance, now in time.
Downbeat	The first beat of a bar. The "one" you count out loud.
Follow	Region mode where the click tracks the playing and the audio is left exactly as recorded.
Lock	Region mode where the click holds a steady BPM and the audio is stretched to match it.
Region	A stretch of the song running one mode.
Rubato	Playing with deliberate tempo freedom. Leave it on Follow.
Tempo map	A list of where the beats actually fell, so a DAW's bars and beats line up with the performance.
Time-stretch	Changing how long audio takes to play without changing its pitch.

1.	Introduction
2.	Installing and First Launch
3.	Quick Start: Your First Export
4.	Follow and Lock
5.	The Timeline
6.	Regions
7.	Placing the "1"
8.	Time Signature
9.	The Click
10.	Preview and Export
11.	Sending the Tempo Map to a DAW
12.	Saving Projects
13.	Controls Reference
14.	Licensing
15.	Troubleshooting
16.	Specifications
17.	Glossary

CORRIGIT

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