Tutorial Tuesday 7 - Granular Synthesis/Sampling
At its heart, granular synthesis involves the playback of small elements, or ‘grains’, from larger segments of audio. For example, you might start with a long field recording, but only select a small portion of it which can be looped to create exciting new textures and tones. There are near infinite possibilities, as you can change loop speed, playback start points and modulate the samples in real time.
Granular synthesisers are essentially ROMplers, but as a production tool are often shied away from as they can be confusing compared to the subtractive style synthesis we’re often used to. So in this tutorial we’ll build our own sort of granular synthesiser by stacking samplers and treating those as oscillators.
You can always take things further and to new levels of complexity by adding filters, lfos, envelopes etc.
Step 1 - Setting up the samplers
In this tutorial, I’ll be using Ableton Live’s instrument rack and simpler (though obviously this can be implemented with any sampler, and if you’d rather not use an instrument rack you place a simpler/sampler on its own individual track, and route them to a bus).
Step 2 - Load some samples
The next thing to do is to select some samples to create your patch. Obviously, sample selection should be based on the final timbre you want to achieve. So, for example, if you wanted to create a futuristic, mechanoid soundscape, you may select some foley recordings of machinery and hydraulics, in conjunction with some synthetic elements.
Step 3 - Select some grains
The next step is to select a chunk of your sample, and loop it to create a tone. This can then be tuned to an accurate pitch. To do this you can loop a constant tone and then tune your sample accordingly.
Step 4 - Repeat For Each Sampler
Build the remainder of your patch. This may take some experimentation with both sample choice and playback length. You may want to include some longer, evolving sounds as I have above. These should also be loopable. Also ensure that your samples loop seamlessly, and pick wave crossover point to avoid clicks. In Live’s simpler and sampler you have the fade control which helps smooth things out. Again, tune the sample to a specific note, or if you’re feeling adventurous you could tune in intervals like 5ths, and adjust the number of voices accordingly. Don’t worry too much about extreme tuning, the patch can sound granular and lo-fi if you want it to!
Step 5 - Finishing Up
With the instrument rack, you can pan each sampler to taste, as well as applying effects and plugins to each sampler chain. You could also get the samples to interact with each other by using the side chain inputs on some of Live’s plugins, and assign parameters to macros.
Finally, you can apply effects to the whole patch to glue everything together, such as compression and reverb.