Gabriele Beretti (AURAL) speaks for the trees, for they have no tongues. By attaching small sensors to his own plants and routing the ensuing signals to synthesizers, Beretti is quite literally telling us what the trees have to say. Using the plants as his root material, Beretti crafts elegant ambient drone that sounds something like what would have happened if Jóhann Jóhannsson and early Haunt Me-era Tim Hecker ever collaborated. But it’s drone with a twist: the small perturbations and variations not induced by hand but by slight shifts in a plant’s electrical activity. In a music industry that is increasingly inundated by laptop producers, Beretti has taken an interesting step back and gotten as analog as you can possibly get. It’s a compelling concept, to be sure, one that your writer has certainly fallen for.

We’ve invited AURAL to answer a few questions about his project.

What sparked the idea for this project?

While watching a performance of Robert Aiki Aubrey Lowe, I saw him feeding his Eurorack through a plant. I instantly got interested and fell in love with the idea of making music from plants and successively discovered biodata sonification! I’ve been making electronic music for a while now, with different projects, mainly techno or ambient but I felt that this was something unique and different. I wanted to give it its own identity and I saw the opportunity to bring together science, art, and club culture

Can you explain what biodata sonification is?

I interface with plants with a device called MIDI Sprout. It is based on an Arduino Board using a galvanometer sensor and electrodes that send out small electrical charges from a battery.

When they’re attached to a leaf, they measure the plant’s resistance to this current. When applied to a human this is called galvanic skin response (GSR). GSR readings provide insight into humans’ inner emotional states and actually used in lie detectors.

The electrical impulses from the plants are translated into MIDI signals, which I then use to produce sounds. On the device there is also a small knob which serves as an adjuster of Threshold/Sensitivity. By turning and decreasing the threshold, smaller fluctuations in conductance from the galvanometer (and plant) can be detected; by increasing the threshold, larger fluctuations are required in order to produce notes. During long term installations, I prefer to use a low threshold setting to produce a pleasant babbling stream of MIDI data. For public interactive events with people, I turn the threshold up rather high, which results in MIDI notes only being produced when a person gets very close or physically touches the plant.

Are there certain plants that generate a specific type of noise?

Yes, every plant has its unique signal, which is extremely sensitive and dictated by various factors, including health, time of day, surroundings, etc.

I noticed that these patterns are similar in every group or families of species. For instance, cactus and succulents signals are somehow similar – pretty random and occupying the whole range of octaves in any moment. Flowers have more “linear flows”.

Can you tell us a little bit about the plants you use?

For this album, I used four different type of plants which I carried with me at various exhibitions in Berlin.

Pitcher Plant (Nephentes x Ventrata):

A beautiful carnivorous plant which needs a lot of water and care. Its wild nature and origins got me to imagine jungle landscapes and torrential rains.

I sculpted many sounds around this idea. I took it with me for a live installation in an abandoned bank, recorded the whole session and when I went back to listen it, I found it was the right material for a bunch of tracks.

Eternal Flame (Calathea Crocata):

An elegant flower which almost glows in the dark. I experimented with it during a performance in the gloomy cellars of the ex-coin factory Alte Münze here in Berlin.

The underground room was so cold and humid that stalactites were hanging from the ceiling. People there were having hot drinks and it didn’t took long to realise that the sensitive plant was highly responsive to the humid and warm breath of the crowd interacting and blowing on it, shaping the sound in the room.

Stinger Barb (Polaskia Chichipe):

It is a typical Mexican cactus. When I first got it, I was really excited about experimenting with it for the next performance, but I soon noticed that the tough skin wasn’t providing any signal to the detectors. After various experiments (e.g. pouring a bit of water and exposing it to hot lights) I realised that the cactus was hibernating. The only solution I got to “wake it up” and get its signal was to make a small incision on the trunk. It started right-away a process of regeneration and the signal came on very strongly. I felt really bad about it, so I only recorded one session with it, which turned into a track on the album, with sounds recalling the healing process of the cactus. A few days later a small scar formed where a signal couldn’t pass through anymore. For live exhibitions I used another plant.

Century Plant (Agave Nigra):

This is a species from the family of succulents, defined by its thick and sharp leaves. Those characteristics, the harmful aspect and its sturdy composition inspired me to create those dark, perpetual and almost impenetrable sounds.

What is your setup like when you create these pieces?

I had to experiment a lot and took me two years to find the right setup and workflow, in order to manage this random-not-random signal and make something cool out of it. Considering also the fundamental rule which I imposed to myself for the productions – to use only exclusively the signal incoming from these alive beings, avoiding safe sequences and carrying with me all the unexpected possibilities during improvisations and live performances. It has been a challenge but as result, the listeners can clearly hear that everything is triggered from the same source.

For each tracks in the album, I used different instruments, a mixture of hardware and software. I felt it was right to give a nice contrast between the different vibes of those plants and try to reflect the characteristics and moods into soundscapes.

In this album I used the following hardware:

Clavia Nord Lead 2 Rack, Dave Smith Prophet REV2, Waldorf Blofeld, Roland Mc 303, Korg Volca FM, Arturia Arp 2600, Arturia Modular V, U-he ACE, Eventide sound processors, field recording samples feeding granular synthesis VSTs.

Are there synthesizers that you’ve found pair better with these signals? Nowadays, people are making tracks solely on their laptops, for example, but you’ve taken a step back and gone as analog as you can get. Why is that?

I am always experimenting new ways and possibilities combining hardware and digital. Working with these extremely sensitive beings is not easy and this is why I think that “versatility” is the keyword for a plant-based setup. I enjoy and find satisfying the combination with wavetable synths, granular synthesis and modulars.

At the beginning my idea was to exclusively use analog hardware but after spending months in the studio experimenting, I realised that this limitation was depriving my creativity and flow. Also in terms of live performances, I had to bring all the gears out of the studio and constantly reshaping that, damaging my workflow.

The result is what really matters at the end. I should not limit myself but instead give full-power of expression to this new way of making music.

What’s your favorite plant?

I just recently got involved into this “green world” and I am fascinated by these extremely intelligent and sensitive creatures. I learnt a lot during this time experimenting with plants and my consciousness is radically changed as well as my awareness, pretty much improved. It is funny how most of the people, blinded by superficial routines, almost forgot that plants are alive beings with real senses and a fundamental part of our existence

It is really difficult to pick a favourite with all this diversity. In my last trip to Spain I collected different signals from beautiful wild species. At the moment I am experimenting and working on that bio-data so you will hopefully soon hear the result.