Mutable Instruments Clouds Review
For its price point and size, you’d be hard-pressed to find another module with as much versatility, inspiration, and potential. If your patches need effects, ambient pads, sampling, or even just some texture, Mutable Instruments Clouds is a worthwhile buy.
It’s no surprise that since its inception in 2014, the Clouds module has evolved and become a Eurorack favorite, found in the cases of artists and enthusiasts like Deadmau5, Andrew Huang, and The Flashbulb.
Don’t forget to also check out our review of Mutable Instruments Rings!
Open Source Cloudy Goodness
Thanks to the open-source format Mutable Instruments produces, Clouds has been ‘remixed’ and expanded upon by different manufacturers. You can opt for a smaller form factor (12hp) like Monsoon from Michigan Synth Works that has alternate control layouts, or an expanded one such as Grayscale’s Supercell (34hp) that’s packed with more features and controls. Whichever route one takes, you’ll have a wealth of sound-shaping controls at your fingertips.
Maximum Flexibility
The module’s claim to fame is for its versatility: it samples, it processes, it can be a delay or a reverb, and it can even be an oscillator. And it’s stereo!
Eurorack synths at its core are about freedom and flexibility, and Mutable Instruments Clouds fits this bill perfectly. Unlike some multi-effect devices that focus on quantity over quality, Clouds is a solid, great-sounding option for reverbs, delays, and more. While these functions alone would make any module stand out, Clouds goes much deeper.
There are several hidden modes and advanced features that are covered later in this article, but we’ll start with the basics.
What Is A Texture Synthesizer?
Émilie Gillet, founder of Mutable Instruments, calls Clouds a “texture synthesizer” which is apt considering how much variety it can bring to a modular patch. Even if you start with just a sine wave, Clouds can transform and mangle it into lush, ambient pads or harsh, experimental noise. These textures can be pitched up or down, delayed, or sent into outer space and back! Clouds is a veritable multitool of a module, but it really shines at making interesting granular textures.
Clouds functions primarily as an audio processor – you can think of it as a multi-effects pedal for modular, but it’s highly expressive and interactive. Control voltage inputs for every parameter enable the manipulation of settings on the module without even touching it. This means Clouds can easily interact with other modules and modulation going around a patch and can add cohesion to many different sounds running through it.
Once a sound is patched or “frozen” into Clouds, tweaking the various knobs can create subtle changes or soaring cacophony and then bring it right back down to the original. Part of the beauty of Clouds is in its chaos and unpredictability. It takes a sound and transforms it into something new and inspirational.
(Want to learn more about different types of synthesis? Check out our guide “Wavetable vs FM vs Additive vs Subtractive (Explained Simply)“)
There is nothing else quite like the Mutable Instruments Clouds available on the Eurorack market. The module is almost synonymous with the format, and seldom does one find a case without Clouds or one of its many variations. Despite it being discontinued, you can still find them floating around on places like Reverb.
- Tons of additional features
- Two-channel processing
- Encourages creativity
Granular Processing and Sampling
Clouds digitally creates its textures and soundscapes with a process known as granular synthesis. Granular synthesis is a method of reshaping sound by sampling it and splitting it into many tiny sections usually less than 50 milliseconds long. These sections are called grains, and manipulating them forms the basis of granular synthesis. From there the grains can be played back at different speeds or pitches, and even overlap each other during playback.
This granular audio is what leads to the interesting textures and dynamics created by the module. By default, Clouds applies this processing to whatever audio is currently running through its inputs, creating a live granular effect. But it can also take a sample of audio and “freeze” it in its audio buffer for processing and playback.
Audio is stored in the buffer when the freeze button is pressed. The length and quality of the buffer can be configured by holding down the blend/audio button on the top right of the module. Sample quality and length ranges from 32 kHz / 16 bit at 1 second to 16 kHz / 8 bit at 8 seconds.
Keep in mind that the lower your sample rate the more lo-fi your sample will sound. This means that there’s a trade-off between how long your sample can be and how clean it will sound. However, this is not a huge limitation; Clouds isn’t meant to replace an MPC or a Digitakt, but it is still something to be aware of.
Clouds can store up to 4 frozen audio buffers as well, so if you love a sound you’ve captured and mangled, it can be saved and recalled later. The controls for saving and loading buffers are as follows:
- To save a buffer, press and hold the load/save button, then press the blend/audio button to select a bank, then the load/save button again.
- To recall a saved buffer, short press load/save button, then press the blend/audio button to select a bank, then the load/save button again.
Once audio is stored in Clouds, the possibility for sound design and texturing becomes even more apparent. There are a number of parameters that can be altered via the knobs and buttons on the panel, covered next.
Panel Control Overview
Mutable Instruments Clouds has every control you need to create interesting and musical sounds right away, as well as access to some more complex features with relatively little menu diving. Here are the controls that you’ll find on the front of the module:
Position
This selects where the grain playback starts from. Turning it clockwise goes towards the beginning of the buffer. There is also a CV control input for modulating position.
Size
This is the “grain size” and sets how small each grain is, affecting the overall texture. This can also be modulated with a control voltage.
Pitch
This sets the pitch of the grains, allowing you to do some really cool real-time transposition effects. This is a 1V/Oct affair, so it’s easy to use with sequencers.
Gain
This is the gain for the input audio, before it becomes granular audio. It ranges from -18 dB to +6 dB.
Density
This is the most reactive granular control, and it controls how the grains overlap. At 12:00 no grains are sown and no granular effects added. Turning counter-clockwise adds grains consistently, clockwise adds them randomly. The further the knob is turned the more the grains overlap.
Texture
This changes the shape of the envelope for each grain, and can make things sound quite ‘smooth’ .
Overall, it’s a subtle variation that begins to smear transients after 2:00.
Blend
This is a multifunction knob that controls the parameter selected by the blend / audio button (blend parameters covered below). This knob progressively catches up to previously set values when switching parameters.
Other Controls
Freeze button
- Samples incoming audio into buffer and lights up when pressed
- Clears buffer when pressed again
- Can be triggered via freeze input
Blend/audio button
This selects sample quality and is capable of making things sound lo-fi.
There is a blend parameter which changes depending on the mode:
- Dry/wet controls balance between processed and unprocessed signal, doesn’t affect reverb
- Pan controls amount of random stereo spread applied to grains
- Feedback controls how many grains are sent back through processing, can get out of control quickly
- Reverb amount, lush digital verb. Independent of dry/wet. See Oliverb in hidden modes for more
Load/save button
- Loads and saves stored buffers
- Holds up to 4 buffers
There is nothing else quite like the Mutable Instruments Clouds available on the Eurorack market. The module is almost synonymous with the format, and seldom does one find a case without Clouds or one of its many variations. Despite it being discontinued, you can still find them floating around on places like Reverb.
- Tons of additional features
- Two-channel processing
- Encourages creativity
Granular Patch Ideas
Mutable Instruments Clouds can be a very versatile tool for adding flair to a patch, but the controls can seem intimidating at first. So if you’re stuck on how to start implementing them or just want to know some more specific use cases, here are a few patch ideas:
Simple delay
Set density at around 9:00 and position fully counter-clockwise. Pass an audio source through and slowly bring up feedback to increase the number of repeats.
Size increases the length of the repeats, and the pitch knob can make each repeat ascend or descend in pitch. If the feedback starts to go out of control (it will at some point) simply turn density back to 12:00 to restore order.
One-shot sampler
Freeze your desired sample into the audio buffer, and make sure density is set to 12:00. Feed a gate or trigger into the trigger input and the sample will playback. Change the position knob to alter the start of the sample and experiment with modulating other parameters.
Pseudo Sample and-hold
Need some random modulation for a parameter to add some dynamics to Clouds? When running in mono, the input is normally set to both channels. This means one of the output channels can be patched back into a CV input to modulate a parameter like a sample and hold random voltage. Just remember not to patch outputs to other outputs to avoid damage!
Catch and release
Send varying gates into the freeze input while audio is passed through Clouds. This will result in an interesting interplay between the source signal and constantly freezing and unfreezing buffer. Experiment with different settings on the position knob.
Digging Deeper: Hidden Modes
All of the functions described so far have pertained to the default granular mode, but Mutable Instruments Clouds comes with three other hidden modes that do vastly different things. The alternate modes are accessed by pressing and holding the blend/audio button for 5 seconds, and then pressing again to cycle to the desired mode. In order, they are:
Pitch-shifter/time-stretcher
Probably the most similar to granular mode, but tuned to more carefully recreate and modify frozen sounds. Texture becomes a DJ style high pass/low pass filter.
Looping delay
For a more controlled delay effect, this mode allows direct looping of the buffer without grains. This mode can create sounds similar to analog tape loops.
Spectral processor AKA “madness”
This is perhaps the most complex of the hidden modes, as it utilizes the rare concept of spectral synthesis. Here Clouds captures audio as separate frames of data plotted on the frequency spectrum, and synthesizes a new signal from it. Freezing audio in this mode allows one to swap between several frozen frames of data instead of buffers.
There is also a second firmware option that most Clouds clones come installed with called Parasites by Matthias Puech which adds the following modes as well:
Oliverb
This mode dedicates all of the available controls on Clouds to reverb, perfect for those not quite satisfied with just one control for their verbs. At a glance, some available parameters include pre-delay, size, high and low pass filters, and decay.
Resonator
This mode acts as a small emulation of another Mutable Instruments module, Rings. It has a chord mode, decay controls, and even multiple voice types. Expect resonant sounds that are out of this world!
Mutable Instruments Clouds Alternatives
Perhaps Clouds’ exact feature set doesn’t seem suitable and you still want access to granular synthesis, or you already have one and want to go even deeper.
There are some great Clouds adjacent alternatives out there too. One option is the arbhar by Instruō, a similar granular processor that has a built-in microphone and polyphonic capabilities. Another is Morphagene by Make Noise, a digital tape machine of sorts that can store longer loops, plus there’s a varispeed control.
Arbhar heralds a new generation of granular processing in eurorack. Sampled audio can be chopped into tiny grains, scattered, shaped, re-pitched, reversed and layered for an endless range of audio manipulation from seamless frozen tones to mutated acousmatic madness.
- Multiple buffers
- Great interface
- Useful onset detection
There is also Nebulae from Qu-Bit, which sports a generous 75 MB memory via an onboard flash drive. All these alternative modules are worthwhile purchases that you can use instead of or alongside Clouds.
Mutable Instruments Clouds pairs nicely with any modular setup and this is part of what makes it so great. It’s a versatile, fascinating module that is also very fun and surprising. You should definitely check it out!