Open source · GPL-3.0-or-later · Windows 10 / 11

DJAP – Open-Source DJ Audio Processor

A free Windows loudness and dynamics processor for DJs and producers. Two independent stereo decks on ASIO® (or WASAPI / DirectSound / MME), matching loudness with EBU R 128 / BS.1770 presets, a VST®3 plug-in, and offline WAV rendering — all under GPL-3.0.

Watch: DJAP in three minutes

Before and after, loudness presets, EQs, analysis, Setup, Windows sound and the plug-in.

Open on YouTube · privacy-friendly embed (youtube-nocookie)

What DJAP does

For DJs, deck A and deck B each run their own processing chain with their own preset and leave on their own output pair. Other Windows users can run one stereo channel (Setup → “Processing”). A VST3 plug-in brings the same chain into DJ software, one deck per plug-in. The same code also renders WAV files offline.

Leveller

Slow automatic gain to the loudness preset target (EBU R 128 / BS.1770). Holds during fades and short pauses; recovers after silence.

Compressor + MB compressor

Wide-band soft-knee compressor, then multiband (1–7 bands, flat sum) with per-band recent level.

Tone & shape

Optional bass enhancer, exciter, de-esser and stereo width, plus a separate EQ (bass, low-mid, presence, treble, Auto, Quiet, …).

True-peak limiter

Soft clipper and look-ahead true-peak limiter so the output stays under the ceiling (default −1 dBTP). Bypass is bit-exact with the same delay.

Loudness presets: Gentle −18 … Very Loud −10 LUFS FM / DAB+ / Web Stream media presets Nine shipped EQs ASIO · WASAPI · DirectSound · MME

Screenshots

DJAP main window with two deck strips and meters
Main window — two decks, meters and spectrum
DJAP Setup window for audio devices
Setup — ASIO / WASAPI devices and buffers
DJAP spectrum and EQ window
Spectrum — EQ curve and multiband gains
DJAP analysis window with compressor curve and goniometer
Analysis — compressor, loudness history, goniometer
DJAP loudness preset editor
Loudness preset editor
DJAP VST3 plug-in window
VST3 plug-in — one deck in your DJ software

Download & install

Latest release: DJAP 0.1.316 for Windows 10 / 11 (64-bit). The installer (DJAP-Setup-<version>.exe) puts DJAP on your PC and, if you choose, the VST3 plug-in in the system plug-in folder (all-users install).

Requirements: a Windows 10 or 11 PC (64-bit). For live DJ work an ASIO interface is typical; WASAPI, DirectSound and MME are also supported. Free software — no warranty (GPL-3.0-or-later).

FAQ

Is DJAP free?

Yes. DJAP is free software under the GNU GPL version 3 or later. You can use, study, share and improve it. There is absolutely no warranty.

Who is it for?

DJs who want consistent loudness between decks on an ASIO interface, and anyone on Windows who wants one stereo loudness / dynamics chain, a VST3 plug-in in DJ software, or offline WAV rendering with the same presets.

Which audio APIs does it support?

ASIO, WASAPI (shared or exclusive), DirectSound and MME. With ASIO, a deck’s input may also come from a WASAPI / DirectSound / MME device (for example a virtual cable); clock drift is corrected automatically.

What loudness presets are included?

Five general presets from Gentle (−18 LUFS) to Very Loud (−10 LUFS), plus media presets for FM Station, DAB+ (EBU R 128 −23 LUFS) and Web Stream. Every value can be changed; you can save your own presets.

Where do I get help or report a bug?

Open an issue on the GitHub Issues page, or start from the manuals in the repository.

About

DJAP is developed by Heye Haken. Licence: GPL-3.0-or-later. VST and ASIO are registered trademarks of Steinberg Media Technologies GmbH.

Project home on GitHub: github.com/hghaken/DJAP