The Nalima is part of the TEI 2024 exhibtion, in Cork, Ireland.

The instrument has had a few changes since the previous demo at CHIME - the coil is upgraded to copper/aluminium to circumvent some overheating issues, and the DSP now runs in a control box on a Daisy Patch Submodule.

The paper on the Nalima is here.

This is a open source instrument. The firmware is on github. I will add hardware documentation in the near future.

If you are interested in building or playing a Nalima, please get in touch (info: https://profiles.sussex.ac.uk/p208667-chris-kiefer)

I presented the Nalima at CHIME 2023, along with presentations from Steve Symons and Dimitris Kyriakoudis. There's a brief report here.

This is the abstract:

The Nalima had its first public outing. It melted a bit, but never stopped making noise (cue imminent redesign of voicecoil cooling!)

Introducing uSEQ: a module for livecoding within eurorack. We showed this recently at Bristonica, and here's a video demo.

More info: https://github.com/lnfiniteMonkeys/uSEQ

This is demo i've been working on, the Nalima. It's a feedback / multistable instrument, using a membrane for interaction. I'm going to be demoing this at the CHIME Annual Workshop in December.

These past two weeks, i've been in Scandinavia, at Sound and Music Computing conference in Stockholm, and visiting the Intelligent Instruments Lab in Reykjavik. The project that I presented at SMC was on measuring complexity in time series, using a new technique called Random Projection Complexity (RPC). These are the slides from my presentation:

The paper is here:

Kiefer, C. 2023. Dynamical complexity measurement with random projection: a metric optimised for realtime signal processing. Sound and Music Computing, Stockholm, Sweden, 12-17 June 2023. (https://luuma.net/papers/smc2023_Kiefer_RPC.pdf)

and for a more digestible version, here's the poster from the conference:

The project started out a few years ago, with the CoFlo project, using complexity metrics to manage the behaviour of the feedback cello.

Kiefer, C., Overholt, D. and Eldridge, A., 2020. Shaping the behaviour of feedback instruments with complexity-controlled gain dynamics. In 20th International Conference on New Interfaces for Musical Expression (pp. 343-348). (https://vbn.aau.dk/ws/files/395237786/nime2020_paper66.pdf)

Complexity metrics seem to be good at detecting saturated feedback, and then you can use this information to change the gain of the feedback instrument to help it to stay in playable place. The metric, ETC, that we used for the original CoFlo study, has poor realtime performance, so the SMC paper is about a new metric, RPC, which is significantly faster than ETC for realtime signal processing.

There's C++ code available for the RPC algorithm (https://github.com/chriskiefer/libcccrt), and there's also a SuperCollider UGen in this repository.

This week at IIL, i've been trying out the algorithm, with Giacomo Lepri's Chowndolo and the lab's own Proto-Langspil.

This is a short demo of the Langspil - it's set up as a feedback instrument, and CoFlo is catching the emerging feedback and damping the feedback loop. As a result, you hear a cyclic push-pull between the feedback and the compressor.

When we plugged the RPC analyser into the Chowndolo, it showed some potentially interesting reflections of the movement of the instrument.

I spent a while making recordings of the Proto-Langspil, using complexity analysis as part of different feedback systems - more on this soon.

In December, Brain Dead Ensemble played a set in the Xenakis Networked Performance Marathon, part of about 8 hours of live performances, streamed on Youtube. Alice Eldridge and I played from the same space in the UK, while Thor Magnusson played from Iceland. We used Sonobus to share audio; Thor sent individual channels to mix into the feedback loops from the two feedback cellos. The entire mix was sent to Athens and broadcast on their video stream along with our streams from Zoom.

More info on BDE: http://www.emutelab.org/braindeadensemble/

Today I joined 'Embodied Perspectives on Musical AI' workshop for a short presentation, which asked questions about how we should approach the ecosystem of AI/ML tools in instrument design, and what the value might be of approaching these tools in a more embodied way? The video of the presentation should be available through the live stream recording on the conference website. Here are the slides:

The funded period of Feedback Musicianship Network has come to an end, but we're still working hard on some of the outcomes. This week i'm in Copenhagen with Dan Overholt and Gianluca Ella. We're working on a mini-feedback instrument that we will release as open-source hardware. So far, ingredients include homemade exciters, analog circuits from Nicolas Collin's envelope follower and the Serge waveshaper, and the output gain stage from the Crackle Box.

Welcome to my new website. For years, this site has just been a bunch of links to other places, but i'm trying to get organised and write about my work more, going by the maybe-(not-)true principle that if it's not documented, it didn't happen!