CHECK / free utility

see where your stereo falls apart.

real-time correlation across 40 frequency bands. bass-weighted scoring tells you what will survive a club system, not just a single number.

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as featured on MuseHub

KERN CHECK plugin interface

in action

see what your mix looks like in mono.

CHECK analyzing a stereo mix. the correlation curve shows safe frequencies in mint and problem areas dropping into the red zone. the bass-weighted score reads 55%. REVIEW MIX.

KERN CHECK analyzing a stereo mix, correlation curve with zone coloring

hover the numbered dots to explore the interface

features

what makes CHECK different.

01 / spectral correlation curve

see mono compatibility across 40 frequency bands in real time. not just a single number — a full picture of where your stereo image holds up and where it falls apart.

02 / bass-weighted score

the score weighs low frequencies 3x heavier than highs — because that's where mono collapse actually hurts. if your bass drops below 60%, your low end won't survive a club system.

03 / frequency-focused analysis

the FOCUS knob lets you zoom into LOW, FULL, or HIGH frequency ranges. isolate your bass mono compatibility or check just the stereo highs.

04 / instant mono and side monitoring

MONO button collapses to mono so you hear the damage. SIDE button solos the difference signal — everything that disappears in mono, isolated.

05 / colour-coded curve and bar chart view

the correlation curve changes colour as it crosses zone boundaries — mint where you're safe, amber for caution, red for phase cancel. flip to bar chart mode via the right-click menu to see all 40 ERB bands as discrete coloured rectangles. spot a single problem frequency at a glance.

06 / smart education that names the frequency

instead of generic warnings, CHECK tells you exactly what's happening: "phase cancel around 80 hz. often an out-of-phase kick and bass relationship." three message variants per problem rotate as you iterate, so you learn three common causes per region. bass is treated as more critical than highs because that's where mono collapse actually hurts.

specifications

the numbers.

40 ERB bands
2048-point FFT
zero latency
4 controls
free forever
VST3 / AU / Standalone
bass-weighted mono score
MONO / SIDE output

what people are saying

system requirements

macOS macOS 12+, Intel or Apple Silicon
windows Windows 10+, 64-bit (VST3)
DAW any VST3 / AU compatible host

go deeper

full documentation.

controls, score zones, how spectral correlation works, mono compatibility tips, and installation guide.

read the docs

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