zone-fx

Lightweight, realtime-aware Digital Signal Processing (DSP) units for JudahZone.

Summary

• Implements small, allocation-minimal DSP building blocks intended for realtime use in audio threads.
• Effects expose simple parameter setters so a GUI or host can update values asynchronously.

Where to find the code

• Main FX package: src/main/java/judahzone/fx
• Analysis utilities (FFT / tuner helpers): src/main/java/judahzone/fx/analysis

Key components

•  Gain — simple gain stage
•  EQ — multi‑band EQ wrapper that configures cascaded filters
•  Filter, MonoFilter, StereoBiquad — filter primitives and biquad helper implementations
•  Delay — delay/echo line with feedback and wet/dry controls
•  Chorus — modulation‑based chorus effect
•  Overdrive — distortion/drive algorithms (several styles)
•  Compressor — dynamics compression stage
•  Freeverb — reverb implementation (Freeverb + wrapper)
•  Convolution — impulse‑response (IR) based cab/IR convolution
•  StereoBus — combines per‑channel FX (gain, filters, delays) and manages activation and processing order
•  FX — base utility/interface for effect units and parameter handling
•  Analysis helpers: Analysis, Transformer, Tuner — FFT and pitch‑detection utilities

Design notes

• Minimal allocations and simple APIs to be safe for realtime audio callbacks.
• Parameters are settable from other threads; processing methods do not allocate per-buffer.

Build and checkout notes

• The project is a module of the meta-zone aggregator. Recommended workflow:
  • Clone the parent aggregator:
    • git clone https://github.com/jeffmasty/meta-zone.git
    • cd meta-zone
  • Build everything (recommended):
    • mvn clean package
  • Build only zone-fx (from the parent directory):
    • mvn -pl zone-fx -am clean package
  • If you cd into zone-fx and run mvn package directly, Maven expects the parent meta-zone/pom.xml at the relative path defined in the module pom.

Dependencies and repository notes

• Intended to keep external deps minimal.
• Core deps:
  • zone-core — project core utilities; usually provided via the parent aggregator.
  • TarsosDSP (be.tarsos.dsp) — used for FFT, audio I/O helpers and a tuner utility.
  • lombok — used as a provided compile-time annotation processor.
• If building standalone, add the Tarsos repository to your Maven settings or pom:
  • https://mvn.0110.be/releases (Tarsos `.be` repository).
• When building inside meta-zone, dependency versions and repository entries are managed by the parent pom.xml.

Runtime notes

• zone-fx is a library; runtime requirements depend on the host application that uses it. If used inside the JACK/JNAJack client, native JACK libraries and a running JACK server are required by that client layer (see the zone-jnajack module for JACK-specific runtime notes).
• zone-test provides a JackClient Java-Swing test channel strip that can be applied against a loaded-in MP3 file.

Credits

• Delay, MonoFilter, FreeVerb, Chorus and the 'Smith' OverDrive adapted from Neil C Smith's JAudioLibs.
• Additional Overdrive algorithms ported from JUCEGuitarAmpBasic.
• Compressor ported from Rakarrack.
• Filters/EQ concepts influenced by JackIIR.
• FFT / tuner utilities rely on TarsosDSP.

Reference

• See the top-level application README in the project root and the meta-zone aggregator pom.xml for full build and dependency details.