gFractor

Multi-mode Spectrum Analyzer & Oscilloscope

gFractor is a multi-mode spectrum analyzer and oscilloscope plugin for music producers, mixing engineers, and mastering engineers who need an accurate picture of what's happening across the stereo field — not just left and right, but mid and side, and tonal versus transient content.

Built on the JUCE framework in C++17, gFractor combines a configurable real-time FFT display with a tempo-synced oscilloscope, full stereo metering, and an A/B reference workflow in a single window. The audio path is fully realtime-safe: no allocations or locks occur on the audio thread.

Three Channel Modes

The same generic Primary / Secondary abstraction is used across three analysis modes, so the workflow stays consistent no matter what you're inspecting:

• Mid / Side — separate the mono centre from the stereo sides.
• Left / Right — traditional per-channel view.
• Tonal / Transient — split the signal by content type, with an adjustable transient time constant (0.1–10 ms).

Spectrum Analyzer

• Configurable FFT order from 1024 up to 16384.
• Overlap from 2x to 8x.
• Adjustable decay and spectral slope.
• Infinite peak hold.
• Freeze.
• Loadable / savable target curves for spectrum comparison.
• Right-click-drag Audition Filter for precise bell-filter isolation of any frequency region.

Oscilloscope View

• Tempo-synced time-domain display.
• Optional spectral colouring of the waveform.

Reference Mode

• Sidechain-fed A/B comparison with ghost overlay.
• Momentary reference via held modifier key, for quick before/after checks while mixing.

Stereo Metering

• Goniometer.
• Phase correlation meter.
• Width-per-octave display (10 bands), to see exactly where stereo width lives in the spectrum.

Workflow

• Three themes: Dark, Light, and Balanced.
• Preset system with save, load, rename, and dirty-state tracking.
• Full keyboard control — every major feature has a shortcut, including channel-mode cycling (Tab), view toggling (V), reference (R / Ctrl), freeze (Z), peak hold (H), target curve (T), fullscreen (W), and one-key cycling through slope, decay, overlap, and FFT settings.

Formats

• VST3 (Windows, macOS, Linux).
• AU (macOS).

System Requirements

• MacOS 10.13 or later (Intel and Apple Silicon, universal binary).
• Windows 10 or later (64-bit).
• Linux (64-bit, VST3).

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