Spec Meter — setup & help

Spec Meter sits on a track in your DAW and shows, live, whether your audio meets the three acoustic ACX checks: peak (≤ -3 dB), RMS loudness (-23 to -18 dB), and noise floor (≤ -60 dB). It never touches your audio — it only listens, with zero latency, and it runs fully offline.

Those are 3 of the 9 checks an ACX submission has to pass. The rest — room tone, chapter length, format, sample rate — are file-level checks you can run free on the web version once you export.

Recording is for tracking sessions, and its floor number is the one nothing else shows you: raw recordings are quiet on purpose, and when mastering brings your level up into spec, the room noise comes up with it. The FLOOR row shows that projected figure — what your noise floor will be after mastering — with the raw measurement beside it. A room that reads fine raw can still fail after processing; this tells you at chapter 1, not chapter 20.

Master is for playing back a finished, already-mastered file before you upload it. No projection — every row is graded against the literal spec numbers.

In Recording mode the RMS row is guidance, not pass/fail — level is what mastering fixes. It warns if you're running hot or so quiet that mastering would have to add too much gain.

Each row is one check: a live bar on a dB scale, the current value, and the requirement. The small marks on each scale are the spec limits; the shaded band on the RMS row is the healthy capture range.

✓ passing · ! worth a look (guidance, not failure) · ✗ over spec. The lamp under the rows is the overall verdict — it stays neutral until the plugin has heard enough audio to judge.

“listening…” means exactly that: the floor is measured from the natural pauses in your speech, so the meter needs a few seconds of real narration — including a pause or two — before it has anything honest to report. It will never show a verdict on silence.

Open the DMG you downloaded and double-click Greenlit Spec Meter.pkg. The installer walks you through it and asks for your Mac password once — that's macOS confirming you want to install for everyone on the computer. Nothing to drag, and no folders to find.

It installs both formats at once, so it works whichever your DAW uses: the AU for Logic Pro, GarageBand and TwistedWave, and the VST3 for Reaper, Audacity and others. You don't need to know which one you need.

Then rescan plug-ins in your DAW so it picks up the new plugin:

Logic Pro / GarageBand:it rescans on next launch — quit and reopen it. If the plugin still isn't listed, open Logic's Plug-In Manager and hit Reset & Rescan.

Reaper: Options → Preferences → VST → Re-scan.

Audacity: Effect → Plugin Manager → set Show to All → Rescan, then select the plugin and click Enable if it lists as Disabled — Audacity finds new plugins but leaves them switched off until you enable them.

Upgrading from an earlier version?The installer removes the old copy you dragged in by hand, so the plugin won't show up twice. Quit your DAW before installing — a host holding the old plugin open can keep it from being replaced.

Run the installer and approve the Windows permission prompt — it places the plugin in C:\Program Files\Common Files\VST3, the standard folder every VST3 host checks. Then rescan plug-ins in your DAW (Audacity: Effect → Plugin Manager → set Show to All → Rescan, then enable it if it lists as Disabled).

Antivirus flagged the download? It's a false positive — here's the proof.

The meters accumulate over your session — RMS and the floor are session-wide measurements, the way the spec itself is measured. Reset sessionstarts them fresh; the plugin also resets itself when your DAW's transport jumps back to the start.

Your Recording/Master choice is remembered when you reload a project. Measurements deliberately aren't — every session starts with a clean slate.

Plugin doesn't appear after install: rescan plug-ins in your DAW, and confirm the file landed in the matching folder above — .component for AU, .vst3 for VST3.

Meters aren't moving:the plugin only hears audio on the track it's inserted on — put it on your vocal track (or the master bus in Master mode) and press play or record.

FLOOR stuck on “listening…”: it measures room tone inside speech pauses, so it needs real narration with a natural pause or two. Continuous tone or music has no pauses to measure.

Still stuck? Contact support — include your DAW and OS version.