Personal Reflections on Dendrophone

Photos of Dendrophone by Daniel Gill

Last month, I, alongside colleagues and friends from Queen Mary University of London, took a day out of our busy schedules to visit Hampshire to experience Dendrophone. Created by Dr Peter Batchelor and the Sensing the Forest team, this sound installation “transforms invisible environmental data into an immersive listening experience”, set within the ancient Alice Holt Forest.

Our field trip was described in great detail by Sofia Zahri within an article on this blog. Instead, I wanted to use this opportunity to reflect more personally on my own experiences of Dendrophone, and particularly, how they link to my experiences of autism.

I do not exaggerate when I say that Dendrophone had a profound impact on me on that Friday afternoon. The installation features speakers spread between several trees, playing a live audio stream automatically generated based on live ecological signals from the forest environment. Each of the three signals–sunlight, humidity, and carbon dioxide—is represented with a specific sound and played through the speakers, creating a blended sound.

Many autistic people experience challenges with managing sensory inputs. While the autistic people are constantly bombarded with such sensory information, for me, Dendrophone provided a sweet relief. Instead of the automatic futile attempt to correlate disparate sensory input, my brain worked optimally, linking the sound of the wind through the forest with Dendrophone’s breathing and the sun beating on my back with increased “ticks”.

While laying down below a mighty beech, taking in all these sounds, I felt grounded—quite literally—with the forest. I knew from my lousy GCSE Biology that trees do, in-fact, “breath”, and that they do so with tiny holes under the leaves (to prevent water getting in – perhaps not lousy after all); but it’s not until you hear them breath that you fully realise that they are living things with a job to do and needs to fulfil, like us.

The sunlight level “ticks” had a similar effect: I created a link with the feeling of the sun (I had my eyes closed at this point) and the intensity of these ticks, again successfully grounding myself in the world of the forest. I use “ticks” tentatively throughout this post, as I’m still not certain I was hearing the “correct” thing: the information provided alongside Dendrophone suggests that sun intensity is represented by “smooth versus juddering hissing”, which doesn’t align with the Geiger-counter-like noise which I nonetheless correlated to solar energy.

To me, the breathing of the trees felt very human, and the thought of whether something similar was designed for sunlight energy intrigued me, despite my confusion. Peter was kind enough to answer a few questions via email, so I put this to him:

Dan: I thought the choice to humanise (or animalise) and correlate carbon dioxide levels with a breathing action was really interesting. Was there a similar thought process how you chose to represent sunlight energy with hissing sounds of varying judder?

Peter: My main concern was to be able to clearly differentiate the various types of data. But yes, I suppose intuitively I associated the drone/hiss and judder with ‘vitality’ that would suggest varying degrees of incoming energy depending on pitch and periodicity. I was also influenced by some members of the forest team saying that they might consider the installation site being used for meditation or mindfulness sessions, so I was trying to make the sound materials suitable for that (hence the drone and breathing sounds).

One thing I failed to pick up on, however, was the “‘dry’ and ‘wet’” noises for humidity: perhaps this was because it was a warm and dry day throughout, or perhaps that aspect of the sound was less noticeable for me. It is on this latter point I asked Peter about next.

Dan: Did you involve others in the choice of sound representations? Do you think there is a level of individuality in the best translation of the forest in this way for different humans/cultures/languages?

Peter: There were a few iterations of the installation prior to it ‘solidifying’ into the version you heard. I still have thoughts on how I might have chosen alternative sounds, but (as with all projects) at some point I had to stop fiddling with it! Interpretation is inevitably individual, but I tried to make the sounds relatively neutral in terms of cultural references (or absence thereof).

The final question I put to Peter was about the placement of speakers. The speakers were attached to a number of trees, connected through vine-like cables slung between them. On the day, I thought all the speakers were playing the same audio, as if the forest as a whole was speaking, but as Peter remarked, it’s slightly more complicated than this.

Dan: I noted that all the speakers (at least I thought) were playing the same audio - was this a conscious choice to represent the forest as a whole? Did you consider having different audio per tree which might blend together (or having speakers on a single tree)?

Peter: They’re playing the same type of audio, but each channel is different. In particular for the humidity sounds, which are granular, I wanted to emulate the distributed spatial characteristics of natural phenomena as made up of thousands of spatially distinct events, rather than lots of swooping movement between speakers. In retrospect the latter might have felt more visceral, but I quite like the subtlety of the outcome. As for having speakers in a single tree: this would have made things a lot easier! But I wanted a sense of distributed space. Again, there’s lots of things I would do differently if the opportunity arose to do a similar project again. But these were the solutions I alighted on this time.

Dendrophone allowed me to connect to the forest like never before, and in doing so, provided a space for a clearer and more coherent mind. I leave you with the following account, written as I sat on a tree stump taking in Dendrophone:

While perched on one of many tree stumps, friends and colleagues stand chatting some ten metres away. Above them, parabolic bows hang between trees, carrying electronic signals to a number of speakers. They all play the same audio, as if each tree has its own voice, but they choose to work together. Whilst my fellow forest explorers affix a sign, I sit lazily, surrounded by rustling leaves, overtopped by moaning planes, rejoicing in whistles of the birds and the laughter of friends. The trees breath through the speakers, as if to remind us they are alive. The low breathy sound matches the movement of the air through the forest. As the clock strikes three, a noticeable increase in “ticks” accompanies an increased feeling of sun hitting my back. To get out of the sun, I move below a tree, choosing to lay down amongst the brown carpet of leaves.