A couple of years ago I had great fun putting together the London Geek Community iPhone OSCestra at Open Hack London and I’ve been controlling Ableton Live with iPhone tapped to my guitar as part of 100 robots for a couple of years now so when @andybudd suggested I do a digital music thing for the Brighton Digital Festival I immediately thought that it would be fun to combine the 2 projects by doing a 100 robots performance with audience participation.

The iPhone OSCestra was effectively a distributed collaborative mixing desk with each person controlling the volume and effect parameters on one channel of a playing back Ableton Live set. For the 100 robots performance I wanted to go further and have the audience actually adding parts to the musical performance, so @toastkid and I added extra drum, bass, synth and sample tracks to the 100 robots live set and filled them full of samples that could be triggered by the audience.

While having the samples adjust in tempo to match each song was relatively simple, transposing them to match the key of each song was more complicated. First I built a custom slice to midi preset which mapped the sample transpose to a macro control and used it to slice all of the samples to MIDI tracks, then mapped all of the transpose controls to a single MIDI controller and added a MIDI track which output the appropriate controller value for each song to a MIDI output which was looped back in to Live to transpose the samples.

The next question was how to avoid the performance turning in to a mush if multiple drum tracks or bass parts were playing concurrently. To avoid this we put dummy clips on the normal 100 robots which muted the normal parts when the audience triggered parts were playing. In some cases we let the audience parts add to the music, in others the audience parts would play instead of the normal tracks.

A final question was how to avoid max and I getting lost when the normal parts we play along to were replaced by unfamiliar samples. To deal with this we set the clip quantization on the audience triggered clips to values longer than the clip length. This meant that even if alternate baselines were constantly being launched, we would still hear the normal bassline for a while at the end of each quantization period, so we would know where we were with the track. To tune these settings we did some fuzz testing with semi random MIDI data to see how much madness we could deal with and still manage to play the songs.

With the tests done it was time to perform with 100 robots and 100s of people at the Brighton Dome and Museum.

Many thanks to Steve Liddell for recording the Brighton Museum set, @aral for letting us experiment on his update conference and to everyone who participated and watched. If you’d like to host another performance, please get in touch and if you like the music, please check out the 100 robots blog and consider buying our album from bandcamp.

100 robots first album, “Attack!” is now finished and available to download now from bandcamp. I’m so glad that it is done and very proud of the result. It’s the first album I’ve made since 2005 and the first I’ve produced using Ableton Live, which once again proved to be an amazing piece of software. The ability to quickly cycle through libraries of samples to find the right sound, easy parameter automation and super flexible routing using drum racks were a huge help.

It’s also the first time I’ve tried to put together a big rock/dance production at home which made mastering tricky as we wanted both a big loud rock sound and huge slabs of sub bass. Because the of the huge sub bass, the Fletcher-Munson effect meant that while the RMS loudness of our initial mixes were normal, the a-weighted RMS values were very low, making the mixes sound very quiet when burned to CD.

The mixes couldn’t simply be turned up without clipping or compressing the mixes which would introduce distortion or reduce the dynamic range of the music. Not wanting to get sucked in to the loudness war we ended up in a complicated 3 way trade off between a-weighted RMS, sub bass weight and dynamic range. Audioleak and the Pleasurize Music tools were both really helpful during this process. We ended up with an an album that hit the sweet spot of -14 dBFS A-weighted RMS, has an average dynamic range of DR6 (admittedly less than the recommended DR10) and hopefully still has enough sub bass to work on a big system. A couple of people have commented that it sounds over-compressed, but most people seem to like where we ended up.

I hope you enjoy the album and that you can join us at the launch parties at the Hydrant in Brighton on the 31st of May or at the Maze in Nottingham on the 14th June — they’re going to be great nights!

Incredibly, 100 robots have 4 gigs lined up in the next 3 weeks: tomorrow we’re playing at an electro/rock night at The Freebutt with Bang Bang Eche, Son of Robot and labasheeda, then next Thursday we’re playing at a more hip hop themed night at The Hope with Tactical Thinking and L-Mo. On the 2nd of December we’re playing at the music hack themed £5 App Christmas Special, where I’ll also be giving a talk about my open source guitar mounted iPhone multitouch Mrmr/LiveAPI/OSC wireless Ableton Live interface and then using it to play live. Finally on the 11th of December we’re playing at the Linden Lab Brighton Christmas party along with the other real rock band that formed from the remnants of the all conquering Linden Lab Brighton virtual Rock Band.

Whew. It’s going to be a busy few weeks. If you can come to any of the gigs, please do. It’s going to be fun: we’ll be playing brand new songs including our first excursion in to Rock/Dubstep and trying out new ways of performing. If all the gigs weren’t in Brighton I’d call it a tour…