Granular synthesis can be kind of confusing and unintuitive and tricky to dial in. Mutable Instruments Beads does not hold your hand through that process, but still, it can do a lot of pretty simple and useful things even if you haven’t studied your Xenakis or Roads.
(*) okay they’re not all simple. But most of them should be easy to reproduce and use as a template for experiments. Especially the non-granular ones!
This is definitely not an exhaustive catalog of techniques — there are a lot of possible techniques I just don’t use much and don’t feel qualified to write about, and probably plenty of things I haven’t discovered yet. I may also add more to this page later.
Please note, these patches use the updated firmware, not the 1.0 firmware which was originally on modules sold before May 2021. If you don’t have saturation on the gain in yellow quality mode or filtering on the Size attenurandomizer in delay mode, you have 1.0.
Some of the techniques may translate to Clouds or to other granular processors in a general way, but I make no guarantees.
The audio examples are not meant to be particularly musical, just a general taste of the techniques. In all cases I recorded with DDMF Magic Death Eye and manual level adjustment in post, but no other FX, noise gate, EQ, mastering, etc. I wasn’t careful about eliminating clicks (normally I’ll soften envelope attacks a little or just throw Izotope RX 7 DeClick on the track).
With complex modules I’ve found it can be handy to start from a baseline “init patch” so you know there are no surprises. These are the common ones that I set when I start working with Beads:
- Time, Shape, Feedback, Reverb full CCW.
- Pitch exactly at noon; Density, Size and Mix approximately at noon.
- All attenurandomizers exactly at noon.
- Freeze off, Seed on.
- White quality setting.
- Automatic gain, or adjust gain manually to prevent clipping/saturation.
- Make sure the right output is producing audio, not triggers (hold CV Assign and tap Seed to toggle it).
Several Trigger Output Uses
If you hold the CV Assign button and tap Seed, you toggle the R output from audio to a trigger output which fires every time a grain is seeded. Uses for this include:
- Clock source with Density CCW from noon.
- Square VCO with Density further CCW — the Density CV input follows 1V/OCT.
- Random Trigger Generator with Density CW from noon. *
- Digital Noise with Density further CW. *
- Clock Divider with Density CCW and the Seed input patched.
- Probability Skipper with Density CW and the Seed input patched. *
(*) Make sure Size is not fully CW, which puts Beads into delay mode and makes the right half of Density non-random.
And it can do all of those things while it’s processing or generating audio. You could even patch the trigger output into the audio input to use it as the source, for instance to ping the reverb or perform granular processing on noise.
Simply enough: don’t patch the inputs, and wait about 10 seconds for wavetable mode to kick in. Time and Feedback control the wavetable morphing. The Pitch input is 1V/OCT (attenurandomizer is ignored). The Quality setting affects the wavetable quality, with more noise in the green mode and much more in the red.
Of course reverb works, and if you turn up the Mix, the granular or delay also kicks in. This will work pretty much as it does with an input.
Clipping/Saturation & Character
Patch an audio source into an input — let’s say a simple triangle wave through a VCA with an envelope. Keep the Wet/Dry mix dry and the reverb down, but crank up the manual gain setting (hold Quality + turn Feedback). The character that Beads will impart will depend on the Quality setting — in white and green modes it’ll clip to a square, but in yellow mode it will saturate very nicely, and in red mode it’ll have a heavily lo-fi vibe while also saturating. (To re-enable auto gain, hold Quality for a few seconds.)
Of course, reverb. This is independent of the main effect wet/dry signal. Several reverb parameters are associated with the single reverb parameter (it’s not just a mix level), and also the quality setting.
In general, the white seems to have a touch more predelay, and damps relatively quickly compared to other modes (though it depends on the knob). Green mode seems to have a smoother diffusion (or just more filtering) and takes longer to decay away. Yellow mode seems a little more springy to me, perhaps with minimal diffusion. Red of course has the low bit depth, but cranking up the knob will filter and smooth that away leaving a sort of lo-fi cavernous feel. But these are all subjective.
Delay Mode “non-delay” tricks
Set the Size knob fully CW to put Beads is in Delay mode (*), the mix fully wet, and the Time, Shape and Feedback knobs fully CCW. The audio is fed through with just a tiny amount of latency. (Note, the delay time range varies with the quality mode.) This allows you to:
- Filter: the Size atteunrandomizer in delay mode becomes a DJ style filter, with lowpass to the left and highpass to the right. This can be effective in red mode where it’ll filter away the noise and give you a dark and brooding tone.
- Pitch shifter: use the pitch knob or pitch attenurandomizer/CV input to shift the pitch using a “rotary head” method.
- Tremolo: turn the Shape knob to set the shape and increase Density to slow the “LFO” rate. (Note that Density also increases the latency though.)
(*) it’s not a wholly separate algorithm the way Granular and Looping Delay are on Clouds. But it does alter the rules of buffer playback to make it act like a delay instead of a granular processor, so I am comfortable calling it “delay mode.”
Delay Mode (as typical delay)
With the dry/wet knob not at max or min and a touch of feedback, Beads makes a pretty great delay module. (Again, I usually leave Time at its minimum setting, for the most useful delay ranges.) You can use it unclocked or clocked. The aforementioned filter and pitch shifter apply, as does reverb, as does the shape knob for some rhythmic fading of the delay signal (which can have useful rhythmic effects).
You can clock the delay mode at audio rates from an oscillator. (Set Density to noon to maintain the same rate as the input. Turn it CCW to multiply the frequency, which the manual shows as dividing the time.) If you patch a short noise burst or a quick exponential decay envelope into the input and crank up the feedback to taste, you’ve got yourself a kind of Karplus-Strong synthesis. It’s imperfect (as K-S often is), with the feedback having a tendency to build itself up or else the notes running very short, and the settings can certainly be a bit fiddly. You will absolutely not get sounds as clean as Rings this way. Filter, Shape, quality mode, and the content of the input signal all have their influence. But it’s still fun to play with!
Phase modulation delay
Another semi-advanced trick you can do with some delays, if they’re capable, is to set a very short delay time and then modulate it at audio rate, creating phase modulation. Beads is very good at this. This seems to work best in white quality mode, with Density, Time and Feedback fully CCW, mix at full CW. But you can also play with feedback for some interestingly buzzy variations. And of course as always with PM, the frequency ratio of the modulator to the carrier makes a big difference, and you can modulate the modulation depth.
(Note that there’s a bit of a glitch when the frequency changes; this is because the processed audio has greater latency than the modulation signal. If you want to clean that up, using another delay at exactly the same length could probably do it… good luck! Another possibility is to either use gradual attack times (either on the whole voice, or the modulation signal) — or perhaps mask it with intentionally noisier transients.)
If you engage Freeze in delay mode, it stops writing to its buffer. The buffer length is arbitrary, but the “delay time” (set by Density or by the clock input) determines the playback length of slices. The slice is selected by Time.
This isn’t my usual territory, so I haven’t explored it a lot. But the key seems to be to use a clock into Seed to set the length — perhaps try sending slower clock divisions than your notes. Modulating Time and Density can then be pretty rewarding.
Give Beads a mono audio source and patch the L and R outputs in stereo. Set white quality mode, Size to about 3 o’clock, and Shape about 45 degrees clockwise from noon (so Shape is pointing at the triangle ramp), Density full CW and Mix to taste. Set the pitch attenurandomizer just a TINY bit clockwise from noon. (*) This patch will seed random grains very rapidly but randomly in stereo, smoothly enough you won’t hear individual grains, while modulating their pitch slightly.
(*) On the attenurandomizers there’s a small dead zone around noon that makes it easier to find zero than there would be otherwise. You’ll want to move just a little bit past that. Without any pitch modulation, you will get a sort of comb filtering effect, which might sound good with some material but not as lush as this chorus.
From this patch you can try any of these:
- Adjusting the Shape CCW so the attacks are sharper. This tends to make the chorus “sizzle” a bit.
- Turning Time up just a little bit increases the delay, and can give either a gated reverb or a delayed feel.
- The Time attenurandomizer will scatter the grains in time. If kept subtle so it’s not too chaotic, it’s a sort of psuedo-reverb.
- Turning Size CCW so that the grains are reversed, but long enough to be smooth, gives a sort of reverse-reverb effect.
- Zero the pitch attenurandomizer but turn the Pitch knob up fully and you’ll get a sort of randomized shimmering effect. Not my cup of tea for most things, but you might find it useful or at least briefly amusing 🙂
- You could turn down Density somewhat so the chorused grains are less frequent, randomizing the effect a bit more. Perhaps surprisingly, this tends to make it stand out a bit more.
Drone to Polyphonic(!) Sequence Converter
Patch a droning VCO into the input, a pitch CV source into the Pitch input (with attenurandomizer fully CW) and a trigger source into Seed. Set the mix fully wet and use Size and Shape for envelope control.
One very cool thing about this is it can create polyphonic sequences from a single oscillator. For each grain, the pitch is sampled and held for the duration of the grain. And with sufficient size, multiple grains will overlap and ring out.
Density controls the clock divisions if CCW, which gives you something to modulate to vary your sequences. To CW, it randomly skips seeds and also randomizes the stereo position of the grain. You could also use the Time attenurandomizer for random panning.
You can play with turning up feedback and seeing what effect the pitch has on that.
- You can also engage Freeze, then repatch the drone oscillator so it can do something else in your patch.
- Or you could use the internal wavetable oscillator and still get polyphony from it (but turn the pitch attenurandomizer back to noon to avoid double-modulation).
Psuedo-Envelope and VCA
This is a simpler variation of the above. Instead of sequencing Beads’ pitch and using a drone, we just use any audio source and set mix 100% wet. Trigger seeds to generate an envelope that produces a grain.
If you’re using pitched notes: because the sample buffer has inherent latency even at the minimum time setting, it can help to use a trigger delay to synchronize the envelope with the pitch change.
This is less cool than the previous patch because it can’t create polyphony. It’s kind of just a weird, laggy envelope/VCA… but with tricks like pitch shift or messing with the time or using Density to cut out some triggers. Maybe worth playing with?
Synced Grains (Waveshaping Plus)
Seed can be triggered at audio rate. So let’s trigger it from the same VCO we use as a sound source. Keep Density fully CCW to fire off grains every cycle, or move it closer to noon to reduce grains or CW to randomize them (and also randomize panning).
Size and Shape can have a lot of impact on the timbre and dynamics. We are firmly in granular synthesis territory, where specific effects may be hard to reproduce and you just have to hunt for sweet spots. But here are a couple of “recipes”:
Relatively long size, Density full CCW, Shape generally on the left side. You’ll get a kind of “sizzle” effect.
For a more classic granular / VOSIM / AM technique, reduce the Density so you’re clocking grains at a division of the input frequency and reduce the size to very small grains narrower than one wave cycle. Modulating Pitch can give formant effects.
Generally, the attenurandomizers bring a lot of chaos because these grains are fired very quickly. Time is the most forgiving of them, but it’s still wild. But you could use a slow LFO into time, or a slightly faster one for drunken pitch effects (it’s effectively phase modulation).
Complex Oscillator Tricks
This is similar to the above patch, but instead of locking Seed to the same frequency (or a division) and phase as the input, we use a second oscillator which follows the same pitch sequence but can be offset. A typical complex oscillator makes this easy.
Since we’re adding another dimension of complexity, let’s take some away: only use a very short size and keep Shape at about 11 o’clock. Set all attenurandomizers to noon. All we want to play with now are:
- the frequency ratio of the oscillator that’s clocking Seed.
- Density, which is another way to modify that (a handy way to divide the ratio).
- the Pitch parameter maybe (and its attenurandomizer, just a little bit, particularly if the ratio is high and pitch knob is already up a bit).
- the Wet/Dry mix on Beads. Assign CV to it and use an envelope, since we’re getting almost FM-like effects with it.
Also this is a good time to point out that sometimes it can make sense to modulate the main parameters with envelopes too — I know I tend to forget about that and either use attenurandomizers, LFOs or sequences.
Here’s one I encountered more or less accidentally, which is very dependent on its source material — but I have reasons for bringing it up.
Yellow quality mode with manual gain cranked up for max saturation. Density about 9 o’clock, Feedback about noon, size about 1 o’clock and Shape noon.
Time it at about 9 o’clock, but tweaked to more or less match the rhythm of the incoming sequence (more on this below).
Pitch is about 10 o’clock, but tuned to (dis)harmonize with the source material.
Besides the source sequence, I’m also sequencing Pitch. Most steps are at 0V but a couple steps in the sequence will shift a bit. All tuned by ear of course.
The mix on Beads is at full. I’m filtering Beads externally with both low and highpass filters — which takes the edge off the bright saturated sound — and then mixing the mono source signal back in.
The source for this is a 2-op FM patch from Akemie’s Castle, with envelopes from Inertia on the carrier and modulator. I tried a couple of different timbres and VCO through and they weren’t effective, so this was just one of those lucky combos!
The purpose for sharing this: it can be worthwhile to process Beads’ output separately, then mix it back with the dry signal using other gear. Particularly with filters or EQ if you use heavy saturation/clipping or the red quality mode. This gives you a lot more options to tame the sound, whether you’re going for something like this or more of an ambient wash.
I also wanted to point out that a combination of semi-rapid seeding and some feedback can give a springy, metallic, resonator-like effect.
Granular, Pretending To Be A Delay
While Beads’ delay mode is pretty great, as a granular processor it can also create delay-like effects. Set Density full CCW or full CW, Size about 3 o’clock and Shape about noon. Increasing Time will increase the perceived delay time — but increasing Feedback may or may not sound like delay feedback, or might give more of a ringing sound from the grains themselves.
With the Size knob set CW, reverse grains are played back. This is nice for ambient washy stuff, of course. But if you trigger a seed along with your incoming note and get the timing right to match the envelope and clock — mostly a matter of setting the Size knob, but possibly also Shape — you can get a sort of immediate reverse playback of each note.
Or you can sequence or divide the Seed triggers to spice it up a bit.
Get a sequence going, then tap freeze. Mult your pitch signal to Beads’ Pitch CV (with the attenurandomizer full CW. Don’t clock Seed.
Pick out a particular slice with the Time knob — or randomize, sequence, or modulate it if you like. But a static setting does work pretty well here.
Adjust Size, Shape, Density and Pitch to taste — it’s difficult to give advice here since it’s so content-dependent and there are so many sweet spots to find. For this sort of thing I tend to like the more gravelly sounds achieved by using medium-to-low density and/or shorter grains, and sharper envelopes, to imitate a certain granular pedal from Red Panda.
Shorter sizes are more likely to stay within the expected pitch, while longer ones will have a tendency to create a sort of “feedback pitch shifting” effect, but much tighter and more in control than actual feedback.
Making some minor changes to the timbre of the source signal once you’ve captured your buffer can also add some contrast.