Amplify

Amplify changes the volume of the signal. Some care needs to be taken, though:setting the level too high can make the sound digitally clip, which can produceunpleasant crackles and pops.

BandLimit and BandPass

These are resonant filters which block frequencies around theCutoff point.BandPass can be used to simulate sound passing through an old telephone line ormegaphone. Modulating the BandPass frequency can simulate the sound of a wah-wahguitar pedal, think of the guitar in Jimi Hendrix'sVoodoo Child (SlightReturn).

Capture

The Capture effect copies the audio frames of the audio bus that it is on intoan internal buffer. This can be used to capture data from the microphoneor to transmit audio over the network in real-time.

Chorus

As the name of the effect implies, the Chorus effect makes a single audio samplesound like an entire chorus. It does this by duplicating a signal and veryslightly altering the timing and pitch of each duplicate, and varying thatover time via an LFO (low frequency oscillator). The duplicate(s) are thenmixed back together with the original signal, producing a lush, wide, andlarge sound. Although chorus is traditionally used for voices, it can bedesirable with almost any type of sound.

Compressor

A dynamic range compressor automatically attenuates (ducks) the level of the incomingsignal when its amplitude exceeds a certain threshold. The level of attenuationapplied is proportional to how far the incoming audio exceeds the threshold.The compressor's Ratio parameter controls the degree of attenuation.One of the main uses of a compressor is to reduce the dynamic range of signalswith very loud and quiet parts. Reducing the dynamic range of a signalcan make it fit more comfortably in a mix.

The compressor has many uses. For example:

• It can be used in the Master bus to compress the whole output prior to being hit by a limiter, making the effect of the limiter much more subtle.

• It can be used in voice channels to ensure they sound as even as possible.

• It can besidechained by another sound source. This means it can reduce the sound levelof one signal using the level of another audio bus for threshold detection.This technique is very common in video game mixing to "duck" the level ofmusic or sound effects when in-game or multiplayer voices need to be fully audible.

• It can accentuate transients by using a slower attack.This can make sound effects more punchy.

Delay

Digital delay essentially duplicates a signal and repeats it at a specifiedspeed with a volume level that decays for each repeat. Delay is great forsimulating the acoustic space of a canyon or large room, where sound bounceshave a lot ofdelay between their repeats. This is in contrast to reverb,which has a more natural and blurred sound to it. Using this in conjunctionwith reverb can create very natural sounding environments!

Distortion

Makes the sound distorted. Godot offers several types of distortion:

• Overdrive sounds like a guitar distortion pedal or megaphone. Sounds distorted with this sound like they're coming througha low-quality speaker or device.

• Tan sounds like another interesting flavor of overdrive.

• Bit crushing clamps the amplitude of the signal, making it sound flat and crunchy.

All three types of distortion can add higher frequency sounds to an original sound, making it stand out better in a mix.

EQ

EQ is what all other equalizers inherit from. It can be extended with Customscripts to create an equalizer with a custom number of bands.

EQ6, EQ10, EQ21

Godot provides three equalizers with different numbers of bands, whichare represented in the title (6, 10, and 21 bands, respectively).An equalizer on the Master bus can be useful for cutting low and highfrequencies that the device's speakers can't reproduce well.For example, phone or tablet speakers usually don't reproducelow frequency sounds well, and could make a limiter or compressorattenuate sounds that aren't even audible to the user anyway.

Note: The equalizer effect can be disabled when headphones are plugged in, giving the user the best of both worlds.

Filter

Filter is what all other filters inherit from and should not be used directly.

HardLimiter

A limiter is similar to a compressor, but it's less flexible and designed toprevent a signal's amplitude exceeding a given dB threshold. Adding a limiter to the final point ofthe Master bus is good practice, as it offers an easy safeguard against clipping.

HighPassFilter

Cuts frequencies below a specificCutoff frequency.HighPassFilter is used to reduce the bass content of asignal.

HighShelfFilter

Reduces all frequencies above a specificCutoff frequency.

Limiter

This is the old limiter effect, and it is recommended to use the new HardLimitereffect instead.

Here is an example of how this effect works, if the ceiling is set to -12 dB, and thethreshold is 0 dB, all samples going through get reduced by 12dB. This changes thewaveform of the sound and introduces distortion.

This effect is being kept to preserve compatibility, however it should be considereddeprecated.

LowPassFilter

Cuts frequencies above a specificCutoff frequency and can also resonate(boost frequencies close to theCutoff frequency). Low pass filters can beused to simulate "muffled" sound. For instance, underwater sounds, soundsblocked by walls, or distant sounds.

LowShelfFilter

Reduces all frequencies below a specificCutoff frequency.

NotchFilter

The opposite of the BandPassFilter, it removes a band of sound from thefrequency spectrum at a givenCutoff frequency.

Panner

The Panner allows the stereo balance of a signal to be adjusted betweenthe left and right channels. Headphones are recommended when configuring in this effect.

Phaser

This effect is formed by de-phasing two duplicates of the same sound sothey cancel each other out in an interesting way. Phaser produces apleasant whooshing sound that moves back and forth through the audiospectrum, and can be a great way to create sci-fi effects or DarthVader-like voices.

PitchShift

This effect allows the adjustment of the signal's pitch independently of itsspeed. All frequencies can be increased/decreased with minimal effect ontransients. PitchShift can be useful to create unusually high or deep voices.Do note that altering pitch can sound unnatural when pushed outside of anarrow window.

Record

The Record effect allows the user to record sound from a microphone.

Reverb

Reverb simulates rooms of different sizes. It has adjustable parameters that canbe tweaked to obtain the sound of a specific room. Reverb is commonly outputtedfromArea3Ds(seeReverb buses), or to applya "chamber" feel to all sounds.

SpectrumAnalyzer

This effect doesn't alter audio, instead, you add this effect to buses you wanta spectrum analysis of. This would typically be used for audio visualization.Visualizing voices can be a great way to draw attention to them without justincreasing their volume.A demo project using this can be foundhere.

StereoEnhance

This effect uses a few algorithms to enhance a signal's stereo width.