Check – Spectral Mono Analyzer

Tired of your 808s hitting hard in your studio monitors, only to completely fall apart when you play the bounce on a phone or in the whip? We have all been there. You cook up a track, dial in some ultra-wide stereo synths to make the vibe feel huge, but the second the track collapses to mono, your low end vanishes into thin air.

Phase cancellation is a silent mix killer, and standard stereo meters usually just give you a single, vague readout that leaves you guessing where the clash is actually happening.

Why Check is a Game-Changer for Your Mix & Workflow

Kern Audio dropped Check to end the guessing game for good. Instead of squinting at a generic phase meter, this tool gives you real-time surgical insight into how your stereo spread translates:

Pinpoint Problem Frequencies in Real Time: The 40-band spectral correlation curve shows you the exact frequency pockets where your stereo field is holding strong and where it begins to fold in on itself – no more blind EQ cuts.
Keep Your Bass Club-Ready: It features a bass-weighted score that weighs low frequencies 3x heavier than the highs. If your low-end reading drops below 60%, you instantly know your sub won’t survive a club sound system.
Focus Exactly Where It Matters: The FOCUS knob lets you isolate LOW, FULL, or HIGH frequency zones so you can zero in on mud in the bottom end or tame excessive stereo widening on your lead vocals and hats.
Audit the Damage Instantly: Quick-toggle MONO and SIDE buttons let you hear the phase cancellation firsthand. The SIDE button solos the difference signal – isolating everything that gets stripped away when summed to mono.

⚡ Pro Producer Tip: Solo The Sides To Clean Up Headroom

Throw Check on your master chain and hit that SIDE button. If you hear heavy sub-bass rumble or punchy kick transients lingering in the sides, drop a mid-side utility on those individual channels and high-pass the side signal up to around 100 Hz. You’ll instantly preserve mono punch, clear out mud, and unlock tons of clean headroom for your limiter.

Tech Specs (Keep it Light)

File Size: Lightweight at just 21 MB
Formats: VST3 and AU compatible hosts
macOS: Version 12 or higher (Intel & Apple Silicon native)
Windows: Windows 10 or higher (64-bit only)

The Verdict

Every producer needs a reliable sanity check on their master bus before sending tracks off to mastering or streaming. Kern Audio’s Check takes the mystery out of mono compatibility and gives you direct control over your phase response. It is clean, dead simple to read, and won’t cost you a dime.

Visit Developer Site

CHECK ( 21 MB )

Let me know in the comments how this sits in your latest project! Did Check expose any sneaky phase cancellation in your low end? Let’s talk shop below! 👇

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