Notes from the Audio Developer Conference

I’ve spent the last couple of days at the 2017 Audio Developer Conference organised by ROLI. This is a get-together and technical conference for people who work on audio software and software-driven-hardware, in practice mostly people working on music applications.

I don’t go to many conferences these days, despite working in academia. I don’t co-write many papers and I’m no longer funded by a project with a conference budget. I’ve been to a couple that we hosted ourselves at the Centre for Digital Music, but I think the last one I went to anywhere else was the 2014 Linux Audio Conference in Karlsruhe. I don’t mind this situation (I don’t like to travel away from my family anyway), I just mention it to give context for why a long-time academic employee like me should bother to write up a conference at all!

Here are my notes — on things I liked and things I didn’t — in roughly chronological order.

The venue is interesting, quite fancy, and completely new to me. (It is called CodeNode.) I’m a bit boggled that there is such a big space right in the middle of the City given over to developer events. I probably shouldn’t be boggling at that any more, but I can’t help it.
Nice furniture too.

The attendees are amazingly homogeneous. I probably wouldn’t have even noticed this, back when I was tangentially involved in the commercial audio development world, as I was part of the homogeneity. But our research group is a fair bit more diverse and I’m a bit more perceptive now. From the attendance of this event, you would conclude that 98% of audio developers are male and 90% are white people from northern Europe.
When I have been involved in organising events in academia, we have found it hard to get a speaker lineup that is as diverse as the population of potential attendees (i.e. the classic all-male panel problem). I have failed badly at this, even when trying hard — I am definitely part of the problem when it comes to conference organisation. Here, though, my perception is the other way around: the speakers are a closer reflection of what I perceive as the actual population than the attendees are.

Talks I went to:

Day 2 (i.e. the first day of the talks):

• The future is wide: SIMD, vector classes and branchless algorithms for audio synthesis by Angus Hewlett of FXpansion (now employed by ROLI). A topic I’m interested in and he has clearly done solid work on (see here), but it quickly reached the realms of tweaks I personally am probably never going to need. The most heartening lesson I learned was that compilers are getting better and better at auto-vectorisation.
• Exploring time-frequency space with the Gaborator by Andreas Gustafsson. I loved this. It was about computing short-time constant-Q transforms of music audio and presenting the results in an interactive way. This is well-trodden territory: I have worked on more than one implementation of a constant-Q transform myself, and on visualising the results. But I really appreciated his dedication to optimising the transform (which appears to be quicker and more invertible than my best implementation) and his imagination in rendering it (reusing the Leaflet mapping API to display time-frequency “maps”). There is a demo of this here and I like it a lot.
  So I was sitting there thinking “yes! nice work!”, but when it came to the questions, it was apparent that people didn’t really get how nice it was. I wanted to pretend to ask a question, just in order to say “I like it!”. But I didn’t, and then I never managed to work up to introducing myself to Andreas afterwards. I feel bad and I wish I had.
• The development of Ableton Live by Friedemann Schautz. This talk could only disappoint, after its title. But I had to attend anyway. It was a broad review of observations from the development of Live 10, and although I didn’t learn much, I did like Friedemann and thought I would happily work on a team he was running.
• The amazing usefulness of band-limited impulse trains by Stefan Stenzel of Waldorf. This was a nice old-school piece. Who can resist an impulse train? Not I.
• Some interesting phenomena in nonlinear oscillators by André Bergner of Native Instruments. André is a compelling speaker who uses hand-drawn slides (I approve) and this was a neat mathematical talk, though I wasn’t able to stay to the end of it.

Day 3 (second and final day of talks):

• The human in the musical loop (keynote) by Elaine Chew. Elaine is a professor in my group and I know some of her work quite well, but her keynote was exactly what I needed at this time, first thing in the morning on the second day. After a day of bits-driven talks, this was a piece about performers and listeners from someone who is technologically adept herself, and curious, but talks about music first. Elaine is also very calm, which was useful when the projector hardware gave up during her talk and stopped working for a good few minutes. I think as a result she had to hurry the closing topic (about the heartbeat project) which was a pity, as it could have been fascinating to have expanded on this a bit more.
  Some of what Elaine talked about was more than a decade old, and I think this is one of the purposes of professors: to recall, and to be able to communicate, relevant stuff that happened longer ago than any current research student remembers.
• The new C++17, and why it is good for you by Timur Doumler. The polar opposite of Elaine’s talk, but I was now well-cushioned for it. C++17 continues down the road of simplifying the “modern-language” capabilities C++ has been acquiring since C++11. Most memorable for me are destructuring bind, guaranteed copy elision on value return, variant types, and filesystem support in the standard library.
  Destructuring bind is interesting and I’ve written about it separately.
• The use of std::variant in realtime DSP by Ian Hobson. A 50-minute slot, for a talk about which Timur Doumler’s earlier talk had already given away the twist! (Yes you can use std::variant, it doesn’t do any heap allocation.) Ambitious. This was a most satisfying talk anyway, as it was all about performance measurements and other very concrete stuff. No mention of the Expression Problem though.
• Reactive Extensions (Rx) in JUCE by Martin Finke. I have never used either React or JUCE so I thought this would be perfect for me. I had a question lined up: “What is JUCE?” but I didn’t dare use it. The talk was perfectly comprehensible and quite enlightening though, so my silly bit of attitude was quite misplaced. I may even end up using some of what I learned in it.