Extension accuracy tips

The HZ Detect Chrome extension measures tuning in real time while you stream, and like any live measurement, the quality of the input decides the quality of the reading. A few habits — mostly about what you capture and when — separate clean, repeatable results from noisy ones.

Capture audio directly, not through the air

The extension can listen three ways: a browser tab, desktop audio, or your microphone. Whenever possible, use the first two.

• Tab capture for anything playing in the browser — YouTube, YouTube Music.
• Desktop audio for apps outside the browser — Spotify, Apple Music, Pandora.
• Microphone only when the sound exists outside your computer.

Direct capture hands the detector the actual signal. A microphone hands it the signal plus your room: speaker coloration, background noise, reflections, whatever else is humming nearby. None of that helps a pitch measurement, and all of it disappears the moment you switch to tab or desktop capture. If you’re setting up for the first time, detect tuning while streaming covers the capture options end to end.

Let it listen longer than feels necessary

Detection works by sampling notes and matching them against tuning tables for 440 Hz, 432 Hz, and the Solfeggio anchors. More samples mean a steadier estimate, so don’t treat the first number that appears as the verdict. Let the track keep playing and watch the reading settle. A value that holds through a verse and a chorus is worth far more than one that flashed up in the first few seconds.

Point it at melodic material

The detector needs pitched content. Verses, choruses, sustained chords, and clear lead lines are ideal. Drops, drum breaks, risers, and percussion-heavy intros give it almost nothing to work with. If you start measuring during a breakdown, just wait — the reading will firm up when the harmonic content returns.

Know which content resists detection

Some tracks won’t produce a confident reading no matter how well you capture them, and the extension is designed to say so:

• Ambient, spoken word, and percussion-heavy tracks often lack enough pitched material to measure. Expect “Uncertain” — that’s the detector declining to guess, which is correct behavior, not a malfunction.
• DJ mixes and live sets are a different trap: the pitch can genuinely vary across the recording, as tracks are tempo- and pitch-adjusted into each other or a live performance drifts. A single reading may be true only for the passage you measured. Treat each track or section within a mix as its own measurement.

Reading the number that comes back

The extension reports the A4 reference the music aligns to. 440 Hz is the modern standard (ISO 16, 1955); 432 Hz sits about 32 cents below it, where a cent is 1/100 of a semitone; the Solfeggio anchors have their own table entries. If you’re unsure what a readout implies — or how close counts as “at” a tuning — how to read detection results breaks it down.

Cross-check surprising results

When a reading contradicts a track’s label, the reading is usually right — mislabeled uploads are common. But confirming costs little:

• Run the same passage through the homepage detector at /#detector; it uses the same on-device approach and accepts mic, tab, or desktop-audio input.
• On a phone, the mobile app detects the tuning and also identifies the song, which helps when you suspect an upload isn’t the version it claims to be.

If a “432 Hz” upload keeps reading 440 across tools and across passages, you’ve measured the truth of it.

When the reading isn’t the tuning you want

The extension tells you what a track is; it can’t change it. If you want the music at a different reference, that’s a retuning job: take a copy you own and convert it from its measured tuning to your target, or use a real-time retuning player while you stream. The options — batch conversion, in-browser converters, and live players — are compared at /retune/.

Next step

Open the extension, play something melodic that you know well, capture the tab rather than the mic, and let the reading settle through a full section of the song. That one deliberate measurement will tell you more about your music’s real tuning than any label ever will.