Joseon · real-time audio analyzer for macOS and Windows

See what you hear.

Joseon reads the sound your computer plays and shows what is in the music and what your headphones must deliver. It only listens. Nothing changes, nothing is recorded, nothing is sent.

Download for macOS Reading the release list…
Download for Windows Reading the release list…

FreeOpen source, GPLv3No accountNo analyticsNo driver

The background is a spectrum. Pick what it listens to.
What it shows

Every panel, from the sound your computer plays right now.

Play music in any app. Joseon shows it. All the details →

Spectrum

Log spectrum

Peak hold, long-term average, note readout.

Spectrogram

The last minutes as a picture

Click a moment: every panel shows it.

Loudness

LUFS and true peak

Range, PLR, PSR, clip count, band energy.

Stereo field

Vectorscope and placement

Correlation and balance, per band.

Headphones

What they must deliver

Measured response, the spectrum at your ear, stress flags.

Session

Timeline and compare

A/B snapshots, now playing, mini spectrum in the menu bar or tray.

The Joseon window: spectrum with headphone overlay, spectrogram, stereo placement, loudness and peak, and the session timeline
The whole window: spectrum, spectrogram, stereo placement, loudness and peak, session timeline.
The spectrum panel of Joseon with the headphone overlay
Spectrum with the headphone overlay.
Three panels of Joseon: spectrogram, stereo placement by frequency, loudness and peak meters
Spectrogram, stereo placement, loudness and peak.
Where it sits

A read-only copy at the mixer.

Joseon asks the operating system for a copy of the mix. Your audio path keeps the same bits and the same latency. No driver, no virtual device. How the tap works →

Player app Qobuz · Spotify · game Operating system mixer Core Audio · WASAPI DAC interface · dongle Amp if you have one Phones your ears Joseon reads a copy process tap · loopback read-only: nothing is written back
Privacy and security

What Joseon does with your data: nothing.

  • No account, no analytics, no telemetry.
  • No recording. Audio stays in memory, on your computer.
  • One network request: the release list on GitHub, to offer updates. Switch it off in Settings.
  • Microphone only when you start a headphone measurement.
  • Open source under the GPLv3. Checked against the source on 2026-10-13.

The full statement, how to check each claim, and the signing status →

Download

Free, open source, one file.

Download for macOS Reading the release list…
Download for Windows Reading the release list…
macOS
  1. Open the dmg, drag Joseon to Applications.
  2. First start: System Settings → Privacy & Security → Open Anyway.
  3. Allow "System Audio Recording". Play music.
macOS 14.4 or later · Apple silicon
Windows
  1. Unzip anywhere. Start Joseon.exe.
  2. First start: More info → Run anyway.
  3. Play music or a game.
Windows 10 or 11, 64-bit · Direct3D 12

Installing, updating and building from source →