CloudChamber lets you hear your sounds played in the Reverberation Chamber at the National Physical Laboratory in London, UK. One by one, submitted sounds are
played out of a pair of loudspeakers into the chamber and simultaneously recorded in stereo with a pair of measurement microphones. The recordings are then uploaded to the CloudChamber
soundcloud page for all to hear, and a direct link to the recording is tweeted to the submitter. CloudChamber was originally built for Music Hack Day London 2009, and has been rewritten over
the last couple of weeks (June 2014) for Music Hack Day 2014 at Sonar+D in Barcelona, Spain. While our software is doing all the hard work in London, we’ll be at the Music Hack Day
stand at the Sonar+D MarketLab exhibition at Sonar By Day - come and say hi!
What is the Reverberation Chamber?
The Reverb Chamber is one of several acoustic measurement facilities in the Acoustics department of the National Physical Laboratory in London, UK.
Put simply, its a big empty room with very hard walls, floor and ceiling and no parallel surfaces. This means sound in the chamber bounces around a lot, and therefore the chamber has a very
long reverberation time - a measure of for how long a sound is present in a room after whatever was making the sound has stopped making it. Reverberation times in the chamber are longest at
low frequencies - over 30 seconds! Frustratingly, as soon as anyone goes into the chamber to try to hear this amazingly long reverberation, their body absorbs some of the sound and reduces
the reverberation time. So CloudChamber is a rare chance to hear the chamber as it’s meant to be! Scientists at the National Physical Laboratory use the Reverb Chamber to generate
‘diffuse acoustic fields’ - an acoustic environment where sound no longer has any particular direction in which it is travelling, and instead will travel in all directions with
equal probability. They do this by ‘filling’ the room with noise which bounces around everywhere, creating a stable acoustic environment. This is useful for determining properties
of acoustics equipment such as measurement microphones, since it can be assumed that the sound pressure level (or loudness) in the room does not change (much) with position. The Reverb
Chamber is also notable for how quiet it is inside (when nothing is making any sound of course). The chamber has very thick concrete walls, and is mounted on springs inside a second much
larger chamber, also with thick concrete walls. This stops sound and vibration getting into the chamber from the outside and means that the sound pressure level in the chamber is less than 0
dB - that means it’s quieter than what most people would hear as absolute silence.
What sound should I submit?
Thinking carefully about what might sound interesting inside the chamber. Something made up of short, crisp sounds with a lot of space will be drastically
transformed and probably sound great. The changes to long, sustained sounds will be more subtle but maybe equally interesting. Why not record your own voice or some sounds from wherever you
happen to be using the SoundCloud app or website, and submit the link here?
When will the sound I submitted be processed?
We can only process sounds overnight and at the weekend (otherwise we’d be disturbing the scientists!). At the moment, the system
is expected to go live at about 1800 BST on Thursday 12th June 2014 and then again for the whole weekend from 1800 BST Friday 13th 2014 June. We’re accepting submissions the whole time,
and probably even after the weekend for next time the system goes live. You can use the time processed and time submitted to work out roughly when your track might get processed, but if you
haven’t been tweeted by Monday 16th June, then your track won’t get processed for a while.
How can I use CloudChamber for my cool sounding space?
CloudChamber is portable, and we'd love to set it up in your cool sounding space. Get in touch at firstname.lastname@example.org