Fourier Compressor

Automatic spectral compression.

The Fourier Compressor from Reflex Acoustics is a digital audio effect plugin that uses the Fast Fourier Transform to implement a 100-band mid/side compressor.

Every frequency band continuously adjusts its threshold and make-up gain in response to the incoming level, so that the device compresses quiet and loud signals equally, and imprints a consistent dynamic signature over time even if input levels change.

This results in a compressor that, although versatile and configurable, can also produce good results on its default settings without needing to be manually calibrated.

Depending on the source material, the effect can sound more transparent than single-band compression—improving dynamics and clarity with less of an overall pumping sound—given that not all frequencies are in gain reduction at the same time.

The device also works as a spectral ducking tool when used in Sidechain mode. Because all selected frequencies experience gain reduction over time, the Fourier Compressor offers a different de-masking sound than other spectral plugins that focus mostly on the loudest or most-clashing frequencies.

Features:

• Automatic compression threshold—use the "Compression" dial to control how far the thresholds ride below the peaks in your signal
• Globally adjustable Attack/Release times (100% on the Attack dial is calibrated to preserve transients but attenuate shortly thereafter)
• Attack time and Ratio vary depending on frequency
• External sidechain ducking capability with 7ms look-ahead
• Parallel processing via gain-matched dry/wet mix control
• Plugin tries to maintain matched short-term LUFS (measured over the trailing 3s), even while you adjust the dials
• Mid-side processing (100% unlinked)

How to use:

• Set the release time to best match the groove of your material
• Use the Smoothing dial if needed to average gain-reduction across adjacent frequency bands
• If desired, drag the red bars in the gain reduction display to narrow the processing to a specific frequency range
• The Mix dial has a sweet spot at 33% wet
• Click the gain reduction display for instant A/B test (still uses CPU as if plugin activated)
• Connect a sidechain signal to use the device in ducking mode (in the AU plugin version, also click "Sidechain" in the lower left of the display)
• Double-click a dial to reset it to its default value, or hold <CTRL>/<CMD> to fine-tune
• Use the Fourier Compressor on your master bus or on individual audio tracks or buses

Technical notes:

• Available in VST3 format for PC, and VST3 & AU formats for Mac. AAX support coming soon
• Requires a compatible Digital Audio Workstation or other plugin host
• 37ms latency from frequency detection window, plus 7ms from look-ahead if used in sidechain ducking mode
• Supports common sample rates from 44.1 to 384kHz
• Plugin is designed for common audio signals such as music and voice; may not react meaningfully to artificial test signals such as chirps, impulses or bursts

Please download and evaluate the free demo version of the Fourier Compressor before purchasing, as we don’t yet offer refunds. Demo version here.

See here for information about versions and changes.