Audio Filters

DisGoLink supports a wide range of audio filters to modify playback. This guide covers all available filters and how to use them.

Applying Filters

Filters are applied using the WithFilters() option:

import "github.com/disgoorg/disgolink/v3/lavalink"

// Create filters
filters := lavalink.Filters{
    Volume: &lavalink.Volume(0.8),
}

// Apply to player
err := player.Update(ctx, lavalink.WithFilters(filters))
if err != nil {
    log.Printf("Failed to apply filters: %v", err)
}

Available Filters

Volume

Adjust the player volume (independent of the player volume setting):

volume := lavalink.Volume(1.0) // 100% volume
filters := lavalink.Filters{
    Volume: &volume,
}

// 50% volume
volume = lavalink.Volume(0.5)

// 150% volume (may cause distortion)
volume = lavalink.Volume(1.5)

Range: 0.0 to 5.0 (0% to 500%)

Equalizer

Adjust 15 bands of frequencies:

Bass Boost
Treble Boost
Flat (Reset)

equalizer := &lavalink.Equalizer{
 0.2,   // 25 Hz
 0.15,  // 40 Hz
 0.1,   // 63 Hz
 0.05,  // 100 Hz
 0.0,   // 160 Hz
 -0.05, // 250 Hz
 -0.1,  // 400 Hz
 -0.1,  // 630 Hz
 -0.1,  // 1000 Hz
 -0.1,  // 1600 Hz
-0.1,  // 2500 Hz
-0.1,  // 4000 Hz
-0.1,  // 6300 Hz
-0.1,  // 10000 Hz
-0.1,  // 16000 Hz
}

filters := lavalink.Filters{
    Equalizer: equalizer,
}

equalizer := &lavalink.Equalizer{
 -0.1,
 -0.1,
 -0.1,
 -0.05,
 0.0,
 0.0,
 0.0,
 0.0,
 0.05,
 0.1,
0.1,
0.15,
0.2,
0.2,
0.25,
}

// Remove equalizer
filters := lavalink.Filters{
    Equalizer: nil,
}

Band Frequencies:

Band	Frequency
0	25 Hz
1	40 Hz
2	63 Hz
3	100 Hz
4	160 Hz
5	250 Hz
6	400 Hz
7	630 Hz
8	1 kHz
9	1.6 kHz
10	2.5 kHz
11	4 kHz
12	6.3 kHz
13	10 kHz
14	16 kHz

Gain Range: -0.25 to 1.0

Timescale

Change speed, pitch, and rate:

Nightcore Effect
Slowed + Reverb
Chipmunk Voice

timescale := &lavalink.Timescale{
    Speed: 1.2,   // 20% faster
    Pitch: 1.2,   // Higher pitch
    Rate:  1.0,   // Normal rate
}

filters := lavalink.Filters{
    Timescale: timescale,
}

timescale := &lavalink.Timescale{
    Speed: 0.8,   // 20% slower
    Pitch: 0.9,   // Slightly lower pitch
    Rate:  1.0,
}

timescale := &lavalink.Timescale{
    Speed: 1.0,
    Pitch: 1.5,   // Much higher pitch
    Rate:  1.0,
}

Parameters:

Speed: Playback speed (0.0 < x)
Pitch: Pitch shift (0.0 < x)
Rate: Audio rate (0.0 < x)

Tremolo

Create a trembling/vibrating effect by changing volume:

tremolo := &lavalink.Tremolo{
    Frequency: 2.0,  // How fast the volume changes (Hz)
    Depth:     0.5,  // How much the volume changes (0-1)
}

filters := lavalink.Filters{
    Tremolo: tremolo,
}

Parameters:

Frequency: 0.0 < x (recommended: 0.1 - 10.0)
Depth: 0.0 < x ≤ 1.0

Vibrato

Create a vibrating effect by changing pitch:

vibrato := &lavalink.Vibrato{
    Frequency: 2.0,  // How fast the pitch changes (Hz)
    Depth:     0.5,  // How much the pitch changes (0-1)
}

filters := lavalink.Filters{
    Vibrato: vibrato,
}

Parameters:

Frequency: 0.0 < x ≤ 14.0
Depth: 0.0 < x ≤ 1.0

Rotation

Create an 8D/rotating audio effect:

rotation := &lavalink.Rotation{
    RotationHz: 5, // Rotation speed (Hz)
}

filters := lavalink.Filters{
    Rotation: rotation,
}

Range: Any integer value Common values:

0: No rotation
5: Slow rotation (8D effect)
10: Medium rotation
20+: Fast rotation

Karaoke

Remove or isolate vocals:

karaoke := &lavalink.Karaoke{
    Level:       1.0,
    MonoLevel:   1.0,
    FilterBand:  220.0,
    FilterWidth: 100.0,
}

filters := lavalink.Filters{
    Karaoke: karaoke,
}

Parameters:

Level: Overall effect level
MonoLevel: Mono signal level
FilterBand: Center frequency (Hz)
FilterWidth: Band width (Hz)

Distortion

Add distortion to the audio:

distortion := &lavalink.Distortion{
    SinOffset: 0.0,
    SinScale:  1.0,
    CosOffset: 0.0,
    CosScale:  1.0,
    TanOffset: 0.0,
    TanScale:  1.0,
    Offset:    0.0,
    Scale:     1.0,
}

filters := lavalink.Filters{
    Distortion: distortion,
}

Parameters: All values are float32. Experiment to find desired effects.

Channel Mix

Mix left and right channels:

Mono
Swap Channels
Left Only

// Convert stereo to mono
channelMix := &lavalink.ChannelMix{
    LeftToLeft:   0.5,
    LeftToRight:  0.5,
    RightToLeft:  0.5,
    RightToRight: 0.5,
}

// Swap left and right
channelMix := &lavalink.ChannelMix{
    LeftToLeft:   0.0,
    LeftToRight:  1.0,
    RightToLeft:  1.0,
    RightToRight: 0.0,
}

// Only left channel
channelMix := &lavalink.ChannelMix{
    LeftToLeft:   1.0,
    LeftToRight:  0.0,
    RightToLeft:  0.0,
    RightToRight: 0.0,
}

Parameters:

LeftToLeft: Left input to left output
LeftToRight: Left input to right output
RightToLeft: Right input to left output
RightToRight: Right input to right output

Range: 0.0 to 1.0 for each parameter

Low Pass

Suppress higher frequencies:

lowPass := &lavalink.LowPass{
    Smoothing: 20.0, // Higher = more suppression
}

filters := lavalink.Filters{
    LowPass: lowPass,
}

Range: 1.0 < x Common values:

20.0: Light filtering
50.0: Moderate filtering
100.0: Heavy filtering

Plugin Filters

Some Lavalink plugins add custom filters:

filters := lavalink.Filters{
    PluginFilters: map[string]any{
        "echo": map[string]any{
            "delay":  0.5,
            "decay":  0.3,
        },
    },
}

Consult your plugin’s documentation for available filters.

Combining Filters

You can apply multiple filters simultaneously:

filters := lavalink.Filters{
    Equalizer: &lavalink.Equalizer{
        0: 0.2,
        1: 0.15,
        2: 0.1,
    },
    Timescale: &lavalink.Timescale{
        Speed: 1.2,
        Pitch: 1.2,
        Rate:  1.0,
    },
    Rotation: &lavalink.Rotation{
        RotationHz: 5,
    },
}

err := player.Update(ctx, lavalink.WithFilters(filters))

Removing Filters

To remove all filters:

// Empty filters struct
filters := lavalink.Filters{}
err := player.Update(ctx, lavalink.WithFilters(filters))

Or remove specific filters:

// Get current filters
filters := player.Filters()

// Remove equalizer but keep others
filters.Equalizer = nil

err := player.Update(ctx, lavalink.WithFilters(filters))

Practical Examples

Bass Boost Command

func bassBoost(player disgolink.Player, enabled bool) error {
    filters := player.Filters()
    
    if enabled {
        // Apply bass boost
        filters.Equalizer = &lavalink.Equalizer{
            0: 0.2,
            1: 0.15,
            2: 0.1,
            3: 0.05,
        }
    } else {
        // Remove equalizer
        filters.Equalizer = nil
    }
    
    return player.Update(context.TODO(), lavalink.WithFilters(filters))
}

Nightcore Effect

func nightcore(player disgolink.Player, enabled bool) error {
    filters := player.Filters()
    
    if enabled {
        filters.Timescale = &lavalink.Timescale{
            Speed: 1.2,
            Pitch: 1.2,
            Rate:  1.0,
        }
    } else {
        filters.Timescale = nil
    }
    
    return player.Update(context.TODO(), lavalink.WithFilters(filters))
}

8D Audio Effect

func eightD(player disgolink.Player, enabled bool) error {
    filters := player.Filters()
    
    if enabled {
        filters.Rotation = &lavalink.Rotation{
            RotationHz: 5,
        }
    } else {
        filters.Rotation = nil
    }
    
    return player.Update(context.TODO(), lavalink.WithFilters(filters))
}

Soft Audio (Low Pass)

func soft(player disgolink.Player, enabled bool) error {
    filters := player.Filters()
    
    if enabled {
        filters.LowPass = &lavalink.LowPass{
            Smoothing: 20.0,
        }
    } else {
        filters.LowPass = nil
    }
    
    return player.Update(context.TODO(), lavalink.WithFilters(filters))
}

Getting Current Filters

Retrieve the currently applied filters:

filters := player.Filters()

if filters.Equalizer != nil {
    log.Println("Equalizer is active")
}

if filters.Timescale != nil {
    log.Printf("Speed: %.2f, Pitch: %.2f", 
        filters.Timescale.Speed, filters.Timescale.Pitch)
}

FAQ

Next Steps

Plugins

Extend functionality with Lavalink plugins

Error Handling

Handle filter application errors

Get Started

Core Concepts

Guides

Integration

Applying Filters

Available Filters

Volume

Equalizer

Timescale

Tremolo

Vibrato

Rotation

Karaoke

Distortion

Channel Mix

Low Pass

Plugin Filters

Combining Filters

Removing Filters

Practical Examples

Bass Boost Command

Nightcore Effect

8D Audio Effect

Soft Audio (Low Pass)

Getting Current Filters

Next Steps

Plugins

Error Handling

Build docs developers (and LLMs) love

Get Started

Core Concepts

Guides

Integration

​Applying Filters

​Available Filters

​Volume

​Equalizer

​Timescale

​Tremolo

​Vibrato

​Rotation

​Karaoke

​Distortion

​Channel Mix

​Low Pass

​Plugin Filters

​Combining Filters

​Removing Filters

​Practical Examples

​Bass Boost Command

​Nightcore Effect

​8D Audio Effect

​Soft Audio (Low Pass)

​Getting Current Filters

​Next Steps

Plugins

Error Handling

Build docs developers (and LLMs) love

Applying Filters

Available Filters

Volume

Equalizer

Timescale

Tremolo

Vibrato

Rotation

Karaoke

Distortion

Channel Mix

Low Pass

Plugin Filters

Combining Filters

Removing Filters

Practical Examples

Bass Boost Command

Nightcore Effect

8D Audio Effect

Soft Audio (Low Pass)

Getting Current Filters

Next Steps