VoxaTrace/com.musicmuni.voxatrace.calibra/CalibraEffects

CalibraEffects

Unified audio effects chain for real-time vocal processing.

What Are Audio Effects?

Audio effects transform audio in real-time to improve sound quality or add character:

Noise Gate: Mutes audio below a threshold (removes background noise)
Compressor: Reduces dynamic range (makes quiet parts louder, loud parts quieter)
Reverb: Adds room ambiance (makes vocals sound less "dry")

The effects chain processes audio in order: NoiseGate → Compressor → Reverb

When to Use

Scenario	Preset	Why
Karaoke/singing app	`VOCAL_CHAIN`	Full processing for professional sound
Practice/learning	`PRACTICE`	Minimal processing, hear your raw voice
Voice recording	`VOICE`	Noise gate + light compression
Add reverb only	Builder with `.addReverb()`	Custom chain

Quick Start

Kotlin

// Create with preset
val effects = CalibraEffects.create(EffectsPreset.VOCAL_CHAIN)

// Process audio in-place
effects.process(samples)

// Cleanup when done
effects.release()

Swift

// Create with preset
let effects = CalibraEffects.create(preset: .vocalChain)

// Process audio in-place
effects.process(samples: &samples)

// Cleanup when done
effects.release()

Usage Tiers

Tier 1: Presets (80% of users)

Kotlin

// Default vocal chain
val effects = CalibraEffects.create()

// Specific preset
val effects = CalibraEffects.create(EffectsPreset.PRACTICE)

Swift

// Default vocal chain
let effects = CalibraEffects.create()

// Specific preset
let effects = CalibraEffects.create(preset: .practice)

Tier 2: Config Builder (15% of users)

Kotlin

val config = CalibraEffectsConfig.Builder()
    .addNoiseGate()                              // defaults
    .addCompressor(CompressorPreset.VOCALS)      // preset
    .addReverb(mix = 0.3f, roomSize = 0.5f)      // custom params
    .build()
val effects = CalibraEffects.create(config)

Swift

let config = CalibraEffectsConfig.Builder()
    .addNoiseGate()
    .addCompressor(preset: .vocals)
    .addReverb(mix: 0.3, roomSize: 0.5)
    .build()
let effects = CalibraEffects.create(config: config)

Tier 3: Runtime Adjustment (5% of users)

Kotlin

// Update parameters at runtime
effects.setCompressorThreshold(-15f)
effects.setReverbMix(0.4f)
effects.setNoiseGateThreshold(-45f)

Signal Flow

Input Audio → [Noise Gate] → [Compressor] → [Reverb] → Output Audio
                   ↓              ↓            ↓
            Removes noise    Evens levels   Adds space

Platform Notes

iOS

Expects 16kHz mono audio (use SonixResampler if needed)
Effects use Accelerate framework for optimal performance
Process on audio thread for lowest latency

Android

Expects 16kHz mono audio (use SonixResampler if needed)
Effects use native C++ for performance
Works with AudioTrack and Oboe

Common Pitfalls

Forgetting to release: Call effects.release() to free native resources
Wrong sample rate: Effects expect 16kHz; resample first if needed
Processing stereo as mono: Convert to mono first or process channels separately
Too much reverb: Start with low mix values (0.1-0.2) and increase gradually
Compressor pumping: Lower ratio (2:1) for natural sound, higher (8:1) for limiting