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Gramophone does not include a built-in equalizer. Instead, it delegates to your device’s system equalizer or any installed third-party EQ app by sending a standard Android audio effect control panel intent.

How it works

When you open the equalizer from Gramophone, the app sends an android.media.action.DISPLAY_AUDIO_EFFECT_CONTROL_PANEL intent, including Gramophone’s current audio session ID. The receiving app uses this session ID to attach its audio effects directly to Gramophone’s audio output stream in real time. This approach means:
  • Any app that handles the standard intent will work, not just apps Gramophone explicitly supports.
  • Effects are applied at the system level, so they benefit from hardware acceleration where available.
  • Gramophone itself stays lean — no EQ UI to maintain.

Opening the equalizer

1

Open Settings

Tap the three-dot menu and select Settings.
2

Go to Audio

Select Audio.
3

Open equalizer

Tap Equalizer. Gramophone will launch your device’s equalizer app or present a chooser if multiple compatible apps are installed.

Compatible apps

Any app that declares support for android.media.action.DISPLAY_AUDIO_EFFECT_CONTROL_PANEL will appear in the chooser. Common examples include:
If no equalizer app is installed and your device does not include a system EQ, the equalizer option will have no effect or may show an error. Install a compatible app first.

Audio session management

The audio session ID is managed by EffectWrapper, which tracks the active ExoPlayer audio session. When Gramophone starts a new playback session or the session ID changes, the wrapper notifies connected effects so they can re-attach. This ensures the EQ stays linked to Gramophone’s audio output across track changes.
If your EQ app loses its effect after switching tracks, check whether the app supports session ID change notifications. Most modern equalizer apps handle this automatically.

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