Ambience
17.5 MB
Ambience is a high-quality, open-source algorithmic reverb VST3 plugin built on a 16-channel Feedback Delay Network (FDN) architecture. Designed with professional audio standards in mind, it delivers rich, natural-sounding reverberation ranging from intimate studio rooms to vast concert halls and beyond — with the precision and stability demanded by real-world production environments.
Schroeder, Moorer, Jot — for sixty years, the foundations of commercial reverb have barely moved. The differences are presets and UI.
Ambience reimplements that foundation from primary academic sources — FWHT feedback matrices, nearest-prime delay allocation, Välimäki-Liski 10-band GEQ, ISM-based early reflections. Research-paper DSP, end to end.
Here’s exactly what’s happening inside the box.
FDN CORE
16-channel Feedback Delay Network
A Fast Walsh-Hadamard Transform forms the feedback matrix, delivering dense, colorless diffusion. The 16 delay lines are tuned to mutually coprime primes on a logarithmic scale, eliminating comb-filter artifacts at any room size.
ROOM · HALL · PLATE · SPRING · GOLDFOIL
ROOM1 / ROOM2 / HALL1 / HALL2 / PLATE / SPRING / GOLDFOIL — each algorithm uses a distinct topological routing, Allpass gain structure, and early-reflection pattern. Seven completely different reverb characters.
Stage 2 GEQ — frequency-dependent RT60
Each FDN channel hosts a 10-band biquad GEQ cascade. The plugin solves a Weighted Least Squares system in real time to follow target RT60 curves with surgical accuracy across the full audible band.
ISM-based Early Reflections
Early reflections are generated via the Image Source Method, tuned per algorithm for perceptually accurate pre-echo with full stereo imaging control.
16 independent LFOs
Each of the 16 FDN channels is modulated by an independent bandlimited-noise LFO, initialized via a Golden-Ratio Weyl sequence to guarantee mutually asynchronous, non-periodic motion.
Four saturation characters
Anti-Derivative Anti-Aliasing in four flavors — Warm (Vicanek), Tape (Padé rational), Tube (asymmetric ADAA), Hard (ADAA clip). Texture without aliasing artifacts.
One PRO button unlocks per-band RT60 multipliers from 31 Hz to 16 kHz, Low / Mid / High Tilt EQ, and saturation type selection.
The live RT60 graph overlays the effective curve (orange — including HF Damping & LF Absorption) on top of the preset reference (gray). Mix by looking, not just by listening.
Every world-class hall, studio, plate and spring you’d wish for — modeled and included. No DLC. No upgrades.

 ![]()
Ambience.1.0.1Â Â ( 17 MB )
