CalibraEffects

Unified audio effects chain for real-time vocal processing. Applies noise gate, compressor, and reverb in sequence to audio samples.

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()

Configuration

Effects Presets

Combo presets that configure the entire chain in one step.

Preset	Kotlin	Swift	Gate	Compressor	Reverb	Use Case
Vocal Chain	`EffectsPreset.VOCAL_CHAIN`	`.vocalChain`	-45 dB	3:1 auto-makeup	0.25 mix	Karaoke / singing apps
Practice	`EffectsPreset.PRACTICE`	`.practice`	-50 dB	2:1	None	Learning / practice
Recording	`EffectsPreset.RECORDING`	`.recording`	-40 dB	6:1 auto-makeup	0.15 mix	Voice recording
Dry	`EffectsPreset.DRY`	`.dry`	None	4:1	None	Compression only
Wet	`EffectsPreset.WET`	`.wet`	None	None	0.5 mix	Reverb only
Clean	`EffectsPreset.CLEAN`	`.clean`	-40 dB	None	None	Noise reduction only

Config Presets

Static configurations on CalibraEffectsConfig for common scenarios.

Preset	Kotlin	Swift	Description
Default	`CalibraEffectsConfig.DEFAULT`	`.default`	No effects enabled
Vocal Chain	`CalibraEffectsConfig.VOCAL_CHAIN`	`.vocalChain`	Noise gate + compression + reverb
Practice	`CalibraEffectsConfig.PRACTICE`	`.practice`	Noise gate only
Voice	`CalibraEffectsConfig.VOICE`	`.voice`	Noise gate + light compression

Builder

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)

Builder Methods

Method	Description
`preset(config)`	Start from an existing `CalibraEffectsConfig`
`addNoiseGate()`	Add noise gate with default settings
`addNoiseGate(preset)`	Add noise gate with a `NoiseGatePreset`
`addNoiseGate(thresholdDb, holdTimeMs, timeConstMs)`	Add noise gate with custom parameters
`addCompressor()`	Add compressor with default settings
`addCompressor(preset)`	Add compressor with a `CompressorPreset`
`addCompressor(thresholdDb, ratio, attackMs, releaseMs, autoMakeup, makeupDb)`	Add compressor with custom parameters
`addReverb()`	Add reverb with default settings
`addReverb(preset)`	Add reverb with a `ReverbPreset`
`addReverb(mix, roomSize)`	Add reverb with custom parameters
`sampleRate(rate)`	Set audio sample rate in Hz
`build()`	Build the `CalibraEffectsConfig`

Config Properties

Property	Type	Default	Description
`noiseGate`	`NoiseGateConfig?`	`null`	Noise gate configuration (null = disabled)
`compressor`	`CompressorConfig?`	`null`	Compressor configuration (null = disabled)
`reverb`	`ReverbConfig?`	`null`	Reverb configuration (null = disabled)
`sampleRate`	`Float`	`16000`	Audio sample rate in Hz

Effects Chain

Audio is processed in a fixed order:

Input Audio --> [Noise Gate] --> [Compressor] --> [Reverb] --> Output Audio
                    |                |               |
              Removes noise    Evens levels     Adds space

Each effect is optional. Disabled effects (null config) are skipped.

Noise Gate

Mutes audio below a threshold to remove background noise.

NoiseGateConfig Parameters

Parameter	Type	Default	Description
`thresholdDb`	`Float`	`-40`	Signal level below which gating occurs (dB)
`holdTimeMs`	`Float`	`100`	Time to hold gate open after signal drops (ms)
`timeConstMs`	`Float`	`10`	Envelope follower time constant (ms)

NoiseGatePreset

Preset	Kotlin	Swift	Threshold	Hold	Time Const	Description
Light	`NoiseGatePreset.LIGHT`	`.light`	-50 dB	150 ms	15 ms	Quiet environments
Standard	`NoiseGatePreset.STANDARD`	`.standard`	-40 dB	100 ms	10 ms	Typical background noise
Aggressive	`NoiseGatePreset.AGGRESSIVE`	`.aggressive`	-35 dB	50 ms	5 ms	Noisy environments
Tight	`NoiseGatePreset.TIGHT`	`.tight`	-30 dB	30 ms	3 ms	Maximum noise reduction

Compressor

Reduces dynamic range by attenuating loud sounds and optionally boosting quiet sounds.

CompressorConfig Parameters

Parameter	Type	Default	Description
`thresholdDb`	`Float`	`-20`	Level above which compression begins (dB)
`ratio`	`Float`	`4`	Compression ratio (e.g., 4.0 = 4:1)
`attackMs`	`Float`	`10`	Time to reach full compression (ms)
`releaseMs`	`Float`	`100`	Time to release compression (ms)
`autoMakeup`	`Boolean`	`false`	Automatically compensate for gain reduction
`makeupDb`	`Float`	`0`	Manual makeup gain when autoMakeup is false (dB)

CompressorPreset

Preset	Kotlin	Swift	Threshold	Ratio	Attack	Release	Description
Vocals	`CompressorPreset.VOCALS`	`.vocals`	-20 dB	3:1	15 ms	150 ms	Natural vocal dynamics
Voice Leveler	`CompressorPreset.VOICE_LEVELER`	`.voiceLeveler`	-15 dB	6:1	5 ms	80 ms	Consistent voice volume
Speech	`CompressorPreset.SPEECH`	`.speech`	-25 dB	2:1	20 ms	200 ms	Gentle spoken word
Broadcast	`CompressorPreset.BROADCAST`	`.broadcast`	-10 dB	10:1	1 ms	50 ms	Heavy limiting
Transparent	`CompressorPreset.TRANSPARENT`	`.transparent`	-30 dB	1.5:1	30 ms	300 ms	Preserves dynamics

Reverb

Simulates natural reflections of sound in a space, adding depth and ambiance.

ReverbConfig Parameters

Parameter	Type	Default	Description
`mix`	`Float`	`0.3`	Wet/dry mix (0.0 = dry, 1.0 = fully wet)
`roomSize`	`Float`	`0.5`	Simulated room size (0.0 = small, 1.0 = large)

ReverbPreset

Preset	Kotlin	Swift	Mix	Room Size	Description
Small Room	`ReverbPreset.SMALL_ROOM`	`.smallRoom`	0.2	0.3	Small practice room
Medium Room	`ReverbPreset.MEDIUM_ROOM`	`.mediumRoom`	0.35	0.5	Medium rehearsal space
Large Hall	`ReverbPreset.LARGE_HALL`	`.largeHall`	0.5	0.8	Concert hall ambiance
Dry	`ReverbPreset.DRY`	`.dry`	0.1	0.2	Minimal reverb
Cathedral	`ReverbPreset.CATHEDRAL`	`.cathedral`	0.6	0.95	Cathedral-like spaciousness

Real-Time Parameter Adjustment

Update effect parameters at runtime without recreating the chain.

Kotlin

effects.setCompressorThreshold(-15f)
effects.setCompressorRatio(6f)
effects.setReverbMix(0.4f)
effects.setReverbRoomSize(0.6f)
effects.setNoiseGateThreshold(-45f)
effects.resetReverb()

Swift

effects.setCompressorThreshold(thresholdDb: -15)
effects.setCompressorRatio(ratio: 6)
effects.setReverbMix(mix: 0.4)
effects.setReverbRoomSize(roomSize: 0.6)
effects.setNoiseGateThreshold(thresholdDb: -45)
effects.resetReverb()

Runtime Methods

Method	Parameter	Description
`setCompressorThreshold(thresholdDb)`	`Float`	Update compressor threshold (dB)
`setCompressorRatio(ratio)`	`Float`	Update compressor ratio
`setReverbMix(mix)`	`Float`	Update reverb wet/dry mix
`setReverbRoomSize(roomSize)`	`Float`	Update reverb room size
`setNoiseGateThreshold(thresholdDb)`	`Float`	Update noise gate threshold (dB)
`resetReverb()`	None	Reset reverb state (useful when starting new audio)

Properties

Property	Type	Description
`hasNoiseGate`	`Boolean`	Whether noise gate is active in this chain
`hasCompressor`	`Boolean`	Whether compressor is active in this chain
`hasReverb`	`Boolean`	Whether reverb is active in this chain

Factory Methods

Method	Description
`CalibraEffects.create()`	Create with default config (`VOCAL_CHAIN`)
`CalibraEffects.create(config)`	Create with a `CalibraEffectsConfig`
`CalibraEffects.create(preset)`	Create with an `EffectsPreset`

Constants

Constant	Value	Description
`CalibraEffects.DEFAULT_SAMPLE_RATE`	`16000f`	Default sample rate for effects processing

Common Patterns

Karaoke Effects Processor

class KaraokeEffectsProcessor {
    private val effects = CalibraEffects.create(EffectsPreset.VOCAL_CHAIN)

    fun processAudioBuffer(samples: FloatArray) {
        effects.process(samples)
    }

    fun setReverbLevel(level: Float) {
        effects.setReverbMix(level)
    }

    fun destroy() {
        effects.release()
    }
}

Dynamic Effects with User Controls

class EffectsController {
    private val effects: CalibraEffects

    init {
        val config = CalibraEffectsConfig.Builder()
            .addNoiseGate(NoiseGatePreset.STANDARD)
            .addCompressor(CompressorPreset.VOCALS)
            .addReverb(ReverbPreset.SMALL_ROOM)
            .build()
        effects = CalibraEffects.create(config)
    }

    // Wire to UI sliders
    fun onReverbMixChanged(value: Float) = effects.setReverbMix(value)
    fun onReverbSizeChanged(value: Float) = effects.setReverbRoomSize(value)
    fun onGateThresholdChanged(value: Float) = effects.setNoiseGateThreshold(value)
    fun onCompThresholdChanged(value: Float) = effects.setCompressorThreshold(value)

    fun release() = effects.release()
}

Swift Practice Session

class PracticeSession {
    private let effects = CalibraEffects.create(preset: .practice)

    func processBuffer(_ samples: inout [Float]) {
        effects.process(samples: &samples)
    }

    func enableReverb() {
        // Note: to add reverb at runtime, create a new chain
        // Runtime methods only adjust existing effects
    }

    func cleanup() {
        effects.release()
    }
}

Conditional Chain with Introspection

val effects = CalibraEffects.create(EffectsPreset.VOCAL_CHAIN)

if (effects.hasReverb) {
    println("Reverb is active")
    effects.setReverbMix(0.2f)
}

if (effects.hasCompressor) {
    effects.setCompressorThreshold(-18f)
}

Platform Notes

Audio must be 16kHz mono. Use SonixResampler to resample if your source audio is 44.1kHz or 48kHz.
The process() method modifies samples in-place for zero-allocation real-time use.

Next Steps

CalibraPitch -- Real-time pitch detection
CalibraVAD -- Voice activity detection
CalibraVocalRange -- Vocal range detection

Quick Start​

Kotlin​

Swift​

Configuration​

Effects Presets​

Config Presets​

Builder​

Kotlin​

Swift​

Builder Methods​

Config Properties​

Effects Chain​

Noise Gate​

NoiseGateConfig Parameters​

NoiseGatePreset​

Compressor​

CompressorConfig Parameters​

CompressorPreset​

Reverb​

ReverbConfig Parameters​

ReverbPreset​

Real-Time Parameter Adjustment​

Kotlin​

Swift​

Runtime Methods​

Properties​

Factory Methods​

Constants​

Common Patterns​

Karaoke Effects Processor​

Dynamic Effects with User Controls​

Swift Practice Session​

Conditional Chain with Introspection​

Platform Notes​

Next Steps​

Quick Start

Kotlin

Swift

Configuration

Effects Presets

Config Presets

Builder

Kotlin

Swift

Builder Methods

Config Properties

Effects Chain

Noise Gate

NoiseGateConfig Parameters

NoiseGatePreset

Compressor

CompressorConfig Parameters

CompressorPreset

Reverb

ReverbConfig Parameters

ReverbPreset

Real-Time Parameter Adjustment

Kotlin

Swift

Runtime Methods

Properties

Factory Methods

Constants

Common Patterns

Karaoke Effects Processor

Dynamic Effects with User Controls

Swift Practice Session

Conditional Chain with Introspection

Platform Notes

Next Steps