Words by Ujin Kim

Christopher Willits is a pioneering electronic musician and producer composing immersive ambient albums on the Ghostly International label – and notably the co-founder & director of Envelop, a nonprofit from San Francisco with a mission to unite people through profound immersive listening experiences. At the forefront of this emerging technology, Christopher Willits is pioneering a new approach toward the creative process and the experiences that immersive audio tools make possible. 

Using space as a compositional element, his compositions from Envelop’s 32-channel venue and audio installations with their open-source spatial audio software. Envelop Live (available in Ableton 10/11) at the heart of it all. 

His work and the Envelop team’s collective efforts express a passion for equity; uniting people through listening experiences and making those experiences accessible for both listeners and creators. Envelop has created the opportunity for immersive audio to serve the future of progressive music culture and beyond.

In this interview, we dive into the unique process and perspective you can build acquiring an understanding of ambisonics and the immersive nature of sound. Dive deeper into the world of immersive audio and innovative tools to record and synthesize a 3D virtual soundfield, like RODE NT-SF1 Ambisonics mic and Envelop for Live in Ableton. 

How did your journey into immersive audio begin? 

For most of my life, I’ve been touring and playing music in various venues worldwide. There are a lot of great spaces, but they are few great listening spaces. For years I dreamed about what the listening space of the future could be, and the intention of listening together – and immersive audio was always a part of the vision. Gratefully some mutual friends shared the passion I felt, and we began to explore deeper. 

Envelop started with a shared love of music and immersive audio. We saw a need to amplify the power of music and its remarkable gift to bring people together through listening. Our first project was designing what would become Envelop for Live, focusing on a mobile listening space. About a year into the project, our friends at The Midway in San Francisco granted us a fantastic opportunity to set up a permanent venue, and we began the plans for Envelop SF. 

We knew that we wanted to have a lot of angular resolution in the soundfield, and the design ended up with 32 speakers, three rings of eight up to twelve feet, with four subs and four speakers on the ceiling. While developing the permanent venue housed at Midway SF, we also created our first mobile space and began taking that to festivals. 

I was lucky enough to experience your first mobile pop-up at FORM Festival back in 2017. What type of spatial audio recordings or source material are you working within these installations? 

Envelop focuses on Ambisonics because it’s a scalable non-proprietary solution for immersive audio, and it sounds amazing. Ambisonics can deploy sound to any number of speakers from one encoded master recording, and there’s a big developer community that’s always innovating the underlying technology. This makes immersive audio more accessible and equitable, in both the tech’s use and the listening experiences that the tools make possible. 

Ambisonics is not a company-owned solution that we must behold ourselves to, and it can integrate into other proprietary immersive audio formats. We want everyone, artists, producers, and listeners, to feel the benefits of immersive audio, and Ambisonics is the most accessible and equitable technical solution to achieve that.

We want to share creativity and allow anyone to use these tools. Envelop’s a free and open-source toolkit, Envelop for Live, has made a noticeable impact on the landscape of immersive audio by providing anyone with a computer and Ableton Live to gain the benefits of three-dimensional music composition and listening. Open-source software allows an entire community to work together to improve the tools and refine and adapt the technology to our collective needs. 

Can you speak on Envelop’s mission of “Listening Together” and music as a medicine? 

Everything in this universe is connected, and listening together allows us to feel that connection emotionally. I believe that listening to music together is one of the most extraordinary things we can do together. It creates group empathy, joy, inspiration. It embodies freedom, celebration, and relaxation all at the same moment.

Music is a powerful medicine that helps us to release emotions and trauma. When we listen and resonate with music, it’s like the universe is listening to us. We’re not alone in this world, we are wholly connected, and we all depend on each other.

As immersive audio becomes more accessible, it will amplify our shared listening experience and the emotional impact of music, which will significantly benefit society. Eventually, as a society, we’re going to understand that everyone and everything is connected. Living in balance with the Earth and each other is not an idealistic dream; it’s a matter of survival. Immersive music creates a space for us to connect with each other and do the work together. 

Ambisonics is the focus of Envelop’s software and listening spaces, sparking this new way of creating and connecting together. What are some pathways for curious composers and spatial enthusiasts to get started? And what are some challenges that have prevented this format from being adopted for over 50 years now? 

Ambisonics’ primary challenge, and for any immersive audio format, is learning the tools and process and understanding how to integrate them into a creative workflow. Envelop’s tools are fun and relatively easy to use, and once you begin to explore the possibilities of sound moving through space, it will change the way you think about composing. We create a lot of classes and workshops for the community, and it’s been great to see where people need more support.

There are generally three ways that an artist or producer can begin working in Ambisonics. 

1. You can use a mic, like the NT-SF1, to record instruments or an environment. 

2. You can take mono or stereo recordings, or samples, and position or move them in 3D 

3. Integrate both of these approaches, which is what I love to do. 

The other main challenge is knowing how to distribute it. The vast majority of the world’s music gear is stereo or mono, but that doesn’t limit us to experiencing music in mono or stereo. For instance, I input my guitar into Ableton Live in stereo or mono and then position the recordings I make, or a live input, within the virtual sphere of Ambisonics using Envelop for Live. 

Many of us have learned audio production within the stereo paradigm, and that’s all entirely relevant for producing great immersive audio. However, it takes a little mental rewiring and experimentation to understand the value of composing, mixing, and performing sound in 3D space. When I began creating music in 3D space, and the movement of sound became a compositional element, it was like I could feel new neural pathways opening up. It fundamentally changed the way I create and think about music. 

Once your immersive music is ready to share, the other challenge is understanding how to export and share it. Envelop for Live gives you the main options for this. You can create a 2ch binaural headphone mix, often called spatial audio, or you can create an encoded Ambisonics mix. This multichannel file decodes for any number of speakers. 

A binaural mix makes the sound feel like it’s around your head. Using signal processing, we can take an encoded Ambisonic mix, and with what’s called an HRTF (head-related transfer function), express that virtual sphere of sound as an illusion of 3D space on headphones. Streaming distribution, like most music, is mostly two channels for stereo playback, but it still works great for a 2ch binaural mix. My last two albums, Horizon and Sunset, are mixed in this way. I’ve done many tests playing stereo vs. spatial audio, and every time, people’s feedback is that a binaural mix heightens the listening experience. 

You mentioned that “Tech is a paintbrush… and using it to make a landscape.” Can you speak on how you can harness this approach when starting a new project? 

Tools are essential, and they are directly related to my process. It’s all about flowing through a process. It’s like a journey into an unknown world, and I’m always learning and growing through that journey. I respect the tools and technology, but I keep my attention on the larger function of the music and the listening experience that I intend. When I surrender to the process, the music, the landscape, the space I’m creating with the listener emerges. I encourage my students to settle on a set of tools that feel best to them, work within those creative constraints, and own the discipline to complete something. If you know “what” and “why,” you’re creating something, or at least hold the space to discover that, the “how,” the process, will be guided by your intuition and focus. Immersive audio benefits what the music becomes and why I’m creating it, to share a space to feel, listen, and be present together. It’s like a sonic paintbrush, and the soundscape we create is the space we unite within. The tools allow us to create what is most important, the social and emotional space we share.

Do you have a specialized toolkit or arsenal of spatial audio tools you use for your compositions? Are you considering how your music will be performed live during your composition process or imagine how people will be listening to it?  

I usually write with my guitar and voice. I’ll record ideas, write out charts, sketches, notes, and just let it flow. Composing for me is a playful ceremony. I set an intention and time to work and explore the space I envision. As I create I imagine what it’s like to share the music live in a multichannel venue like Envelop SF, but I also see people listening on headphones lying on their bed. 

I recently started experimenting with the RODE NT-SF1 Ambisonic microphone and use Envelop for Live’s B-format player to layer that sound into the other mono and stereo tracks that I’m spatializing. I’ll make a recording and start the encoding and decoding process back at Overlap Studios to convert it to b-format. 

The NT-SF1 is the best ambisonic mic I’ve used. The design of it is impeccable, and the sound is excellent. I’ve been using a few other Ambisonic mics over the years, and this is the easiest one to use in the field. The mic creates recordings with a very natural presence to them. Details feel scaled well, whereas some mics seem to overemphasise or underemphasise the edges of sounds. It’s obvious that so much research went into the design of the mic. The quality of the recordings, the ease of use, and solid construction, are unmatched in my experience.

How do you usually start with an idea? And are you working on something special at the moment?

My ideas begin with the intention of the space I wish to create with the listener. This space is the overlapping emotional, spiritual, physical space we share. 

I’m working on an immersive album right now. I began tracking guitar, lines and chords, bass synths, harmonies, voices, and integrating field recordings. I’m gradually mixing and editing as I develop the ideas, which gives me an idea of where different layers will live in 3D space. 

Soon I’ll freeze the editing and composing and focus entirely on finishing the mixes. Once mixing begins, I work with stems or the layers of the composition, and I process and mix those in the Overlap Studio. We have a lot of outboard analog gear that helps me get the right texture and balance on all of the layers. Once the stems are mixed, I create the binaural or spatial audio master, and then I go into Envelop SF and finish the immersive masters, mixing with 32 speakers around me. The mixes then become an encoded multichannel file, and I can work with that or adapt the encoding for different immersive formats.

Are you working on anything right now? How can composers get involved with immersive audio and all the work you’re spearheading?

I’m about to start mixing this album that I’ve been working on through the pandemic. Envelop is working towards some new outdoor events in the coming months, and in-person events in Envelop SF are on the horizon. The new version of Envelop Stream is also in development, and we’re excited about sharing this when it’s all ready. To begin working in immersive audio you can download Envelop for Live. I would love to listen with you in Envelop SF or Envelop Stream.

Join the Immersive Audio Workshop here.