Radioform

A system equalizer for macOS.

Radioform is a free, open-source system equalizer for macOS.
It applies a clean, precise 10-band parametric EQ across everything you play.

Design

Radioform is built as a small set of focused components, each doing one job well:

• DSP Engine (C++)
  Real-time safe processing with a 10-band parametric EQ, preamp, and limiter.

• Audio Driver (CoreAudio)
  A system output device that integrates directly with macOS.

• Audio Host (Swift)
  Handles device management, shared-memory audio transfer, and DSP execution.

• Menu Bar App (SwiftUI)
  A lightweight UI that controls a separate audio host process; no realtime audio in the UI.

What You Can Do

• Apply system-wide EQ across all apps
• Shape sound with a 10-band parametric equalizer
• Adjust per-band frequency, Q, and filter type (Peak, Shelf, Pass, Notch)
• Keep levels safe with limiter and preamp guard rails
• Load bundled presets and save custom presets (JSON on disk), safely validated
• Switch devices without breaking your audio flow

Performance

Radioform is designed to be invisible:

• Under 1% CPU usage on Apple Silicon
• Zero added latency in the signal path
• Clean, transparent audio with extremely low distortion

Getting Started

• Download the latest release from the Releases page
• Select the Radioform output that matches your speakers or headphones
• Adjust, save, and forget about it

For development details, see CONTRIBUTING.md.

License

Radioform is released under the GNU General Public License v3.0.
See LICENSE for details.