The <effects> element

Adding global, instrument-wide effects is easy: just add an <effects> element right below your top-level <DecentSampler> element.

It is also possible to have effects that only get added to a specific group. To adding effects that only apply to a specific group, all you need to do is create an <effects> group that lives underneath the <group> element for the group you want to affect.

Group level effects are initialized every time a note is started and destroyed every time a note is stopped. If you play two notes simultaneously, two instances of this effect will be created and these will be independent of eachother. As a result, they use more CPU than global effects.

NOTE: Only certain effects will work as group-level effects: lowpass filter, hipass filter, bandpass filter, gain, and chorus. Delay and reverb cannot work properly as they will be deleted before their tail peters out.

The <effect> element

Within the <effects> element, you can have any number of <effect> sub-elements. These specify parameters for each individual effect that you would like to have in your global effects chain. There are currently only a handful effects available although more could definitely be added on request:

All <effect> elements support a tags attribute — a comma-separated list of tag names. Tags allow bindings to target effects by name instead of by numeric index. For example:

<effects>
  <effect type="lowpass" frequency="22000" tags="main-filter" />
</effects>

A binding can then reference this effect using tags="main-filter" instead of effectIndex="0":

<binding type="effect" level="instrument" tags="main-filter" parameter="FX_FILTER_FREQUENCY"
         translation="linear" translationOutputMin="100" translationOutputMax="8000" />

Low-pass, Band pass, and Hi-pass filter

A 2-pole resonant filter that can be either a lowpass, bandpass, or highpass filter

Example:

<DecentSampler>
  <effects>
    <effect type="lowpass" resonance="0.7" frequency="22000" />
  </effects>
</DecentSampler>

There is also a single pole version of the lowpass filter that can be accessed using the lowpass_1pl effect type. This version does not have a resonance parameter.

<DecentSampler>
  <effects>
    <effect type="lowpass_1pl" frequency="22000" />
  </effects>
</DecentSampler>

Attributes:

Attribute		Type	Valid Range	Default
type	Required	The type of filter	Must be either lowpass (legacy: lowpass_4pl), lowpass_1pl, bandpass, or highpass
resonance	Optional	The filter resonance (Q)	0.001 - 5.0, where 5 is big, 0 is small.	0.7
frequency	Optional	The filter frequency	0 - 22000	22000

Notch EQ Filter

A simple notch filter.

Example:

<DecentSampler>
  <effects>
    <effect type="notch"  q="0.7" frequency="22000" />
  </effects>
</DecentSampler>

Attributes:

Attribute		Type	Valid Range	Default
type	Required	The type of filter	Must be notch
frequency	Required	The filter frequency	60 - 22000.0	10000
Q	Optional	Q is the ratio of center frequency to bandwidth	0.01 - 18.0	0.7

Peak EQ Filter

A peak filter centred around a given frequency, with a variable Q and gain.

Example:

<DecentSampler>
  <effects>
    <effect type="peak"  q="0.7" frequency="22000" gain="2.0" />
  </effects>
</DecentSampler>

Attributes:

Attribute		Type	Valid Range	Default
type	Required	The type of filter	Must be peak
frequency	Required	The filter frequency	60 - 22000.0	10000
Q	Optional	Q is the ratio of center frequency to bandwidth	0.01 - 18.0	0.7
gain	Required	Values greater than 1.0 will boost the high frequencies, values less than 1.0 will attenuate them.	0 - 1.0	1.0

Gain effect

Applies a volume boost or cut to the output signal.

Example:

<DecentSampler>
  <effects>
    <effect type="gain" level="-6" />
  </effects>
</DecentSampler>

Attributes:

Attribute		Type	Default	Valid Range
type	Required	Must be gain		gain
level	Required	The amount of gain to apply. By default (and for backwards compatibility) this is expressed in decibels (e.g. -6 reduces the signal by ~50%). If levelUnit="linear" is also set, this value is treated as a linear multiplier (e.g. 0.5 reduces the signal by 50%, 1.0 is unity gain, 2.0 doubles it).	0	dB: -99 – 24; linear: 0.0 – 8.0
levelUnit	Optional	Specifies the unit for the level attribute. Valid values are decibels (default, for backwards compatibility) and linear. When set to linear, the level attribute is treated as a linear multiplier rather than a dB value. Note: this attribute must appear before level in the XML element.	decibels	decibels, linear

Reverb effect

Example:

<DecentSampler>
  <effects>
    <effect type="reverb" roomSize="" damping="" wetLevel="" />
  </effects>
</DecentSampler>

Attributes:

Attribute		Type	Valid Range	Default
type	Required	Must be reverb	reverb
roomSize	Optional	The reverb “room size”	0 - 1.0, where 1.0 is big, 0 is small.	0.7
damping	Optional	The reverb damping level	0 - 1.0, where 0 is not damped, 1.0 is fully damped.	0.3
wetLevel	Optional	The volume of reverb signal	0 - 1.0	0

Delay effect

A simple delay effect that can be controlled either in seconds or using musical time increments based on the host tempo. For a complete explanation of how to use tempo-syncing, see here.

Attributes:

Attribute		Type	Valid Range	Default
type	Required	Must be delay	delay
delayTimeFormat	Optional	Determines whether the delay will be synced to DAW tempo or not, as well as what format you will be using for the delayTime parameter. There are two possible values: 1) seconds, which is the default, means that delayTime will be specified in seconds and will not change when the DAW tempo changes; 2) musical_time means that delay time will be specified using an integer value generated by a control which is setup to use the musical_time valueType parameter. In order for this to work, you will need to be using the plug-in within a DAW that provides a tempo to the plug-in.	seconds, musical_time	seconds
delayTime	Optional	The delay time in seconds	0 - 20.0	0.7
feedback	Optional	The feedback level.	0 - 1.0, where 0 is no feedback, 1.0 is max feedback.	0.2
stereoOffset	Optional	The parameter allows you to introduce delay variations between the left and right channels. Half of this amount is subtracted from the left channel’s delay time and half of this amount is added to the right channel’s delay time. For example, if the delayTime is 0.5 seconds and the stereoOffset is 0.02 s, then the actual left channel delay time will be 0.49s and the actual right channel delay time will be 0.51s so that the two channels are offset by 0.02 seconds.	-10 - 10	0
wetLevel	Optional	The volume of the delay signal	0 - 1.0	0.5

Example of using the delay effect when specifying time in seconds:

<DecentSampler>
  <effects>
    <effect type="delay" delayTime="0.5" stereoOffset="0.01" feedback="0.2" wetLevel="0.5" />
  </effects>
</DecentSampler>

Example of using the delay effect when specifying time in musical time:

<DecentSampler>
  <ui>
    <tab>
      <labeled-knob x="180" y="40" label="Delay Time" valueType="musical_time" 
                    minValue="0" maxValue="20" value="10" defaultValue="10">
        <binding type="effect" level="instrument" position="0" parameter="FX_DELAY_TIME" />
      </labeled-knob>
    </tab>
  </ui>
  <effects>
    <effect type="delay" delayTimeFormat="musical_time" delayTime="10" stereoOffset="0.01" 
            feedback="0.3" wetLevel="0.5" />
  </effects>
</DecentSampler>

Chorus effect

Example:

<DecentSampler>
  <effects>
    <effect type="chorus" mix="0.5" modDepth="0.2" modRate="0.2"/>
  </effects>
</DecentSampler>

Attributes:

Attribute		Type	Valid Range	Default
type	Required	Must be chorus	chorus
mix	Optional	The wet/dry mix which controls how much of the chorus signal we hear	0 - 1.0, where 1.0 is just chorus, 0 is just dry signal.	0.5
modDepth	Optional	The modulation depth of the effect	0 - 1.0, where 0 is no modulation, 1.0 is max modulation.	0.2
modRate	Optional	The modulation speed in Hz.	0 - 10.0	0.2

Phaser effect

Example:

<DecentSampler>
  <effects>
    <effect type="phaser" mix="0.5" modDepth="0.2" modRate="0.2" centerFrequency="400" feedback="0.7" />
  </effects>
</DecentSampler>

Attributes:

Attribute		Type	Valid Range	Default
type	Required	Must be phaser	phaser
mix	Optional	The wet/dry mix which controls how much of the phaser signal we hear	0 - 1.0, where 1.0 is just phaser, 0 is just dry signal.	0.5
modDepth	Optional	The modulation depth of the effect	0 - 1.0, where 0 is no modulation, 1.0 is max modulation.	0.2
modRate	Optional	The modulation speed in Hz.	0 - 10.0	0.2
centerFrequency	Optional	The center frequency (in Hz) of the phaser all-pass filters modulation	0 - 22000	400
feedback	Optional	Sets the feedback volume of the phaser.	-1 - 1.0	0.7

Convolution effect

This effect allows you to use a convolution reverb or amp simulation to your sample library. Depending on the length of the impulse response, the convolution effect can use substantial CPU, so you’ll definitely want to do some testing both with and without the convolution effect turned on.

Example:

<DecentSampler>
  <effects>
    <effect type="convolution" mix="0.5" irFile="Samples/Hall 3.wav" />
  </effects>
</DecentSampler>

Attributes:

Attribute		Type	Valid Range	Default
type	Required	Must be convolution	convolution
mix	Optional	The wet/dry mix controls how much of the convolution signal we hear	0 - 1.0, where 1.0 is just convolution, 0 is just dry signal.	0.5
irFile	Required	The path of the WAV or AIFF to use as an Impulse Response (IR) file	String	No default

Pitch Shifter effect

As of version 1.13.3, Decent Sampler contains an old-school pitch shifter effect, which allows you to shift the pitch of the audio signal up or down by a specified number of semitones. This can be useful for creating harmonies or for adding subtle chorus effects.

Attributes:

Attribute		Type	Valid Range	Default
type	Required	Must be pitch_shift	pitch_shift
pitchShift	Optional	The number of semitones to shift the pitch of the audio signal	-24 - 24, where -24 means two octaves down, 0 means no pitch shift, and 24 means two octaves up
mix	Optional	The wet/dry mix controls how much of the pitch-shifted signal we hear	0 - 1.0, where 1.0 is just pitch-shifted signal, 0 is just dry signal.	0.5

Example:

<DecentSampler>
  <effects>
    <effect type="pitch_shift" pitchShift="2" mix="0.5" />
  </effects>
</DecentSampler>

Wave Folder effect

Introduced in version 1.7.2. This effect allows you to fold a waveform back on itself. This is very useful for generating additional harmonic content.

Attributes:

Attribute		Type	Valid Range	Default
type	Required	Must be wave_folder	wave_folder
drive	Optional	The volume of the input signal	1 - 100, where 100 means the signal is amplified by a factor of 100 and 1 means no amplification is applied	1
threshold	Optional	The amplitude above which wave folding should take place	0 - 10.0	0.25

Because wave folding tends to sound better when applied on a per-voice basis, it usually makes sense to set up the wave folder at the group level (separate group effects get created for each keypress). Example:

<DecentSampler pluginVersion="1">
  <ui>
    <tab>
      <labeled-knob x="180" y="40" label="Drive" type="float" minValue="1" maxValue="100" textColor="FF000000" value="1">
        <binding type="effect" level="group" groupIndex="0" effectIndex="0" parameter="FX_DRIVE" translation="linear" />
      </labeled-knob>
      <labeled-knob x="280" y="40" label="Threshold" type="float" minValue="0" maxValue="1" value="1" textColor="FF000000">
        <binding type="effect" level="group" groupIndex="0" effectIndex="0" parameter="FX_THRESHOLD" translation="linear" />
      </labeled-knob>
    </tab>
  </ui>
  <groups>
    <group>
        <!-- Samples go here. -->
    <effects>
        <effect type="wave_folder" drive="1" threshold="1" />
      </effects>
    </group>
  </groups>

Wave Shaper effect

Introduced in version 1.7.2. This effect allows you to distort an audio signal. This is very useful for generating additional harmonic content.

Attributes:

Attribute		Type	Valid Range	Default
type	Required	Must be wave_shaper	wave_shaper
drive	Optional	The amount of distortion. This really just controls the volume of the input signal. The volume of the input signal	1 - 1000, where 1000 means the signal is amplified by a factor of 1000 and 1 means no amplification is applied	1
driveBoost	Optional	Introduces an extra gain boost to the drive	0 - 1.0	1
outputLevel	Optional	The linear output level of the signal	0 - 1.0	0.1
highQuality	Optional	Whether or not oversampling is performed. Oversampling sounds better, but it’s CPU intensive. If you want to save CPU, set this to false.	true, false	true

Because wave shaping tends to sound better when applied on a per-voice basis, it usually makes sense to set up the wave shaper at the group level (separate group effects get created for each keypress). Example:

<DecentSampler pluginVersion="1">
  <ui>
    <tab>
      <labeled-knob x="180" y="40" label="Drive" type="float" minValue="1" maxValue="40" textColor="FF000000" value="0.5473124980926514">
        <binding type="effect" level="group" groupIndex="0" effectIndex="0" parameter="FX_DRIVE" translation="linear"/>
      </labeled-knob>
      <labeled-knob x="280" y="40" label="Drive Boost" type="float" minValue="0" maxValue="1" value="0.328312486410141" textColor="FF000000">
        <binding type="effect" level="group" groupIndex="0" effectIndex="0" parameter="FX_DRIVE_BOOST" translation="linear"/>
      </labeled-knob>
      <labeled-knob x="380" y="40" label="Output Lvl" type="float" minValue="0" maxValue="1" value="0.328312486410141" textColor="FF000000">
        <binding type="effect" level="group" groupIndex="0" effectIndex="0" parameter="FX_OUTPUT_LEVEL" translation="linear"/>
      </labeled-knob>
    </tab>
  </ui>
  <groups>
    <group>
        <!-- Samples go here. -->
      <effects>
        <effect type="wave_shaper" drive="0.5473124980926514" shape="0.328312486410141" outputLevel="0.1"/>
      </effects>
    </group>
  </groups>

Stereo Simulator effect

Introduced in version 1.17.0. This effect converts a mono input signal into a pseudo-stereo signal using one of three classic algorithms.

<effect type="stereo_simulator"
        algorithm="adt"
        width="0.5"
        delayTime="0.005"
        modRate="0.5"
        modDepth="0.3" />

Attributes:

Attribute		Type	Valid Range	Default
type	Required	Must be stereo_simulator	stereo_simulator
algorithm	Optional	Pseudo-stereo algorithm to use	lauridsen, schroeder, adt	adt
width	Optional	Stereo spread and dry/wet amount; 0 = mono/dry, 1 = full stereo effect	0–1	0.5
delayTime	Optional	Delay time in seconds	0.001–0.030	0.005
modRate	Optional	LFO modulation rate in Hz (ADT algorithm only)	0.1–10.0	0.5
modDepth	Optional	LFO modulation depth (ADT algorithm only)	0–1	0.3

The three algorithms are:

• lauridsen: Complementary comb filters — simple and CPU-efficient.

• schroeder: Double-delay comb filters — slightly richer stereo image.

• adt (default): Artificial Double Tracking with LFO-modulated delay — the most convincing stereo widening effect. The modRate and modDepth parameters only affect this algorithm.

The width parameter serves as both the stereo spread amount and the dry/wet control. Setting width to 0 produces a mono dry signal; setting it to 1 applies the full stereo effect.

All parameters except algorithm are bindable. Example with a width knob:

<DecentSampler pluginVersion="1">
  <ui>
    <tab>
      <labeled-knob x="100" y="40" label="Width" type="float" minValue="0" maxValue="1" value="0.5" textColor="FF000000">
        <binding type="effect" level="instrument" effectIndex="0" parameter="FX_WIDTH" translation="linear" translationOutputMin="0" translationOutputMax="1"/>
      </labeled-knob>
    </tab>
  </ui>
  <groups>
    <group>
      <!-- Samples go here. -->
    </group>
  </groups>
  <effects>
    <effect type="stereo_simulator" algorithm="adt" width="0.5" delayTime="0.005" modRate="0.5" modDepth="0.3" />
  </effects>
</DecentSampler>

Bit Crusher effect

The bit crusher reduces the bit depth and sample rate of the audio signal, producing a characteristic lo-fi, digital, crunchy sound. Bit depth reduction introduces quantisation noise, while sample rate reduction creates aliasing artifacts.

<effect type="bit_crusher" bitDepth="8" sampleRateReduction="4" mix="1.0"/>

Attributes:

Attribute		Type	Valid Range	Default
type	Required	Must be bit_crusher	bit_crusher
bitDepth	Optional	The number of bits used to quantise the audio signal. Lower values = more aggressive crushing.	1–24, where 24 is clean and 1 is maximum crushing.	24
sampleRateReduction	Optional	Sample-rate reduction factor. A value of 4 means the effective sample rate is reduced to one quarter of the original.	1–32, where 1 is no reduction and 32 is maximum downsampling.	1
mix	Optional	The wet/dry mix which controls how much of the bit-crushed signal we hear.	0–1.0, where 1.0 is fully crushed and 0.0 is the original dry signal.	1.0

Both bitDepth and sampleRateReduction are bindable, so you can attach knobs to control them in real time.

Binding parameters for the bit crusher effect:

Binding parameter value	Description
FX_BIT_DEPTH	Controls the bit depth (1–24)
FX_SAMPLE_RATE_REDUCTION	Controls the sample-rate reduction factor (1–32)
FX_MIX	Controls the wet/dry mix (0–1)

Example with knobs for all three parameters:

<DecentSampler pluginVersion="1">
  <ui>
    <tab>
      <labeled-knob x="80"  y="40" label="Bit Depth" type="float"
                    minValue="1" maxValue="24" value="24" textColor="FF000000">
        <binding type="effect" level="instrument" effectIndex="0"
                 parameter="FX_BIT_DEPTH" translation="linear"
                 translationOutputMin="1" translationOutputMax="24"/>
      </labeled-knob>
      <labeled-knob x="185" y="40" label="Rate Reduction" type="float"
                    minValue="1" maxValue="32" value="1" textColor="FF000000">
        <binding type="effect" level="instrument" effectIndex="0"
                 parameter="FX_SAMPLE_RATE_REDUCTION" translation="linear"
                 translationOutputMin="1" translationOutputMax="32"/>
      </labeled-knob>
      <labeled-knob x="290" y="40" label="Mix" type="float"
                    minValue="0" maxValue="1" value="1" textColor="FF000000">
        <binding type="effect" level="instrument" effectIndex="0"
                 parameter="FX_MIX" translation="linear"
                 translationOutputMin="0" translationOutputMax="1"/>
      </labeled-knob>
    </tab>
  </ui>
  <groups>
    <group>
      <!-- Samples go here. -->
    </group>
  </groups>
  <effects>
    <effect type="bit_crusher" bitDepth="24" sampleRateReduction="1" mix="1.0"/>
  </effects>
</DecentSampler>