AudioMulch Help > Contraption Reference > Filters Previous Next


Randomly chops up and scrambles live sound with random filtering to create watery sounds (filtered granular synthesis).

Nebuliser is a delay line granulator and granular filter that operates on audio input buffered in a delay line. The buffered audio is chopped into small grains, each of which passes through a bandpass filter. The grains can be output at varying densities, creating clouds of grains ranging from sparse tics to dense drones and textures. Each grain has a randomly determined amplitude, pan, transposition, delay time, feedback, duration, envelope shape, filter cutoff and resonance amount (Q). You can quantize grain onset times to create rhythmic patterns, and the interonset time parameter (IOT) lets you determine the time between the start of one grain and the next. You can also statically sample the delay line with the freeze parameter. The mix (ratio) of the input signal and the granulated sound can also be controlled.

Many parameters make use of range sliders to specify a range of values; in such cases each grain is assigned a random value from within the specified range. A single value is selected for each grain, and the value doesn't change for the lifetime of the grain.

All of the processes above are shared with DLGranulator. The main difference between the contraptions is that Nebuliser also passes each grain through a bandpass filter. You can specify the frequencies of these bandpass filters, as well as the widths of the filters used on each grain.

This contraption synchronizes to the global clock when using the Quant (Quantize) parameters. Remember to press play.

See the Adjusting Contraption Properties section for information about using sliders, knobs, presets etc.

Related Contraptions

DLGranulator, BubbleBlower


Nebuliser parameter editor window



Adjusts the volume of the input signal before it is granulated.



Specifies the range of possible amplitudes available for each grain.



Specifies the range of possible stereo panning locations available for each grain.



Specifies the range of possible sampling delays times available for each grain. Each grain uses a separately selected segment of audio from the delay line. If the minimum and maximum values of Delay are the same, the output will be a granulated version of the input signal, delayed by the amount specified. If the minimum and maximum values of Delay specify a range, this has the effect of time-smearing the input signal (each grain will be assigned a random delay time from the specified range). Delay ranges from 0 to 9.5 seconds.



Specifies how much of the granulated output is fed back into the delay line input.



Specifies the ratio between granulated and input sound.



Specifies the range of possible transposition factors available for each grain. The range is +/- 2400 cents (two octaves) from the original pitch. Positive transposition factors shift the output higher in pitch. Negative factors lower the pitch. Trans affects the rate (speed) at which each grain is played back.



Determines the time from the beginning of one grain to the beginning of the next. If the grain duration (GDur) is less than the interonset time, a particled texture will result. If the grain duration exceeds the interonset time, grains overlap, making it possible to create smooth textures. Interonset time ranges from 0.5 ms to 2 seconds.

Quant (QuantizeAmount)

When the clock is running, Nebuliser allows the onset times of all grains to be quantized. Set the amount of quantization from none (0%) to total (100%). The clock must be running for Quant to work.

Quant. Period


The Quantize Period settings below the Quant slider lets you specify the quantization period (spacing of quantization pulses) as a rhythmic unit multiplied by a number.The clock must be running for grain quantization to work.



Each grain has an amplitude envelope consisting of an attack, sustain and decay portion. Shape determines the duration of the sustain portion relative to the duration of the attack and decay portions. When shape is 0, the envelope is a triangle, when it approaches 1, the attack and decay portions shorten and the envelope becomes more rectangular.



Specifies the range of possible envelope skew factors available for each grain. Skew adjusts the relative duration of the attack and decay portions of the grain envelope. Smaller values of skew decrease the attack time and increase the decay time. Larger values of skew decrease the decay time and increase the attack time.


Pauses input to the delay line, allowing the delay line to be statically sampled for time-freezing effects.

Max Grains (MaxGrains)

Controls the maximum number of simultaneously overlapping grains, ranging from 1-200. Due to the limited processing power of computers, you cannot mix an infinite number of overlapping grains in real time. Even the maximum number of grains in Nebuliser (200), can be too hard for slower computers to mix. Avoid audio glitches on slower computers by lowering the Max Grains setting. Lower settings will, however, result in a thinner texture.



Controls the level of correlation/decorrelation between randomized grain parameters. When set to 0, parameters for a single grain are correlated so that, for example, higher pitched grains are panned to the right. When set to 1, the relationship between grain parameters is decorrelated, or completely random.



Defines the range of possible frequencies from which each grain's bandpass filter center frequency is selected.The frequency range is from 20 – 18,000 Hz.



Defines the range of possible widths for the bandpass filters used on each individual grain. The higher the setting the narrower the range. A narrower range will result in tone-like sounds that ring more, as the filter will accentuate tighter bands of frequencies.

Relevant Example Files

The following files provide examples of how Nebuliser can be used:

TranceRiffer.amh, ChordProgression.amh & MetaSSpatosaurus.amh

To open the Example Files directory, go to the File menu, select Open, and double-click on the Examples folder. Read descriptions of the example files here.

Previous Next