Free mono compatibility plug-in, VST3 and AU
MonoCheck
A plug-in for your master or any bus. It tells you in plain words whether your mix holds in mono, and fixes it in one click when it does not.
MonoCheck listening to a club loop, filmed straight from the plugin. The bass turns wide and the verdict says so. Listen Mono plays the mix the way a club system or a phone will, then one click on the fix puts the low end back in mono and the verdict turns green.
The verdict, in plain words
MonoCheck listens to your mix and names what it hears, with a tip on what to check. A new verdict waits 0.6 seconds before it shows, so it never flickers.
- SafeSafe in mono
- It holds on a mono PA. The verdict also says how many dB quieter the mix gets in mono.
- MonoMono: no stereo at all
- Perfect for a kick, a bass or a lead vocal. A full mix usually wants some width above the low end.
- Very wideVery wide: n dB in mono
- Fine on headphones, thinner on a mono PA. Lower Width or narrow the widest layers.
- Mids cancelPart of the mids cancels in mono
- Vocals, snare and bass harmonics carry a mix in mono: check wideners and doubled parts on them.
- Wide lowsThe low end is wide
- Club systems play the bass in mono: try Mono bass at 120 Hz. One click on the suggested fix applies it.
- CancelsParts cancel in mono (n dB)
- Check the polarity of layered sounds, phase wideners and very wide reverbs.
- CancelsMost of the mix cancels in mono
- One side looks upside down: flip the polarity of one channel at the source, then check again.
Read it
A vectorscope, the correlation of the last 8 seconds for the full mix and the low band, and the correlation of the lows, mids and highs.
You choose where the low band ends, from 60 to 300 Hz, and where the highs start, from 1 to 8 kHz. Mono drop shows how many dB quieter the mix gets in mono, next to balance and peaks.
Compact shrinks the window to a light and one word, Safe, Check or Not safe, so the verdict stays in sight without taking up the screen. One click brings the full window back, and your project keeps the choice.
Hear it
Listen to your mix six ways: Stereo, Mono (left and right summed), Mid (the centre), Side (the edges), the left channel or the right channel on its own. Swap L and R, or flip the polarity of the right channel.
These are for your ears only: the meters keep reading your mix, and offline exports, bounces and freezes skip them.
Fix it
Mono bass puts everything under the frequency you choose in the centre, from Off up to 400 Hz. Width narrows or widens the sides, from 0 to 200 %. Output trims the level from −24 to +12 dB.
The Fix section is printed to the output, and Mono bass and Width never change the mono sum.
Specs
| Type | Mono compatibility analyser, audio effect for a master, a bus or a track |
|---|---|
| Format | VST3 (macOS and Windows) and Audio Unit (macOS) |
| System | macOS 11 or later (Apple Silicon and Intel), Windows 10 or 11 (64-bit) |
| Tested in | Ableton Live |
| Works in | Any DAW that loads VST3 or Audio Unit plug-ins. Not Pro Tools, which only loads AAX. |
| Listen | Stereo, Mono, Mid, Side, Left, Right, Swap L and R, Flip right polarity |
| Meters | Verdict, vectorscope, correlation history (8 seconds), correlation of the lows, mids and highs, mono drop, balance, peaks |
| Fix | Mono bass (Off to 400 Hz), Width (0 to 200 %), Output (−24 to +12 dB) |
| Version | 1.0.1 |
| Price | Free |
Questions
Where do I put MonoCheck?
On your master to check the whole mix, or on any bus or track to check one part. It reads what it receives, after its own Fix section.
Does MonoCheck change my sound?
Only if you use Fix: Mono bass, Width and Output are printed to the output. The Listen buttons, Swap and Flip are for your ears only, and offline exports, bounces and freezes always get your mix.
What do the correlation numbers mean?
+1 is mono, 0 is very wide, and below 0 parts of the mix cancel when left and right are summed. MonoCheck shows it for the whole mix and for the lows, mids and highs.
Why does it suggest Mono bass at 120 Hz?
Club systems play the low end in mono, and 120 Hz is a common place to start. It is only a suggestion: set Mono bass anywhere up to 400 Hz, or leave it off.
Is MonoCheck really free?
Yes. No account and no licence key. You can leave your email to hear about updates, but you do not have to.
Windows says “Windows protected your PC”. What do I do?
The Windows installer is not signed yet. Click More info, then Run anyway. The macOS installer is signed and notarized by Apple.
Download, free
Works in your DAW
- Ableton Live tested
- Logic Pro
- FL Studio
- GarageBand
- Bitwig Studio
- Cubase
- Nuendo
- Studio One
- Fender Studio Pro
- Reaper
- Reason 12.5+
Any DAW that loads VST3 or Audio Unit plug-ins. Logic Pro and GarageBand use the Audio Unit, on macOS. Pro Tools isn’t supported: it only loads AAX.
Double-click the installer, then rescan your plug-ins. The macOS installers are signed and notarized by Apple. The Windows installers are not signed yet: if Windows shows “Windows protected your PC”, click More info, then Run anyway.