Direct Line audio for FFT

advanced
#1

Hi All !

I’ve been playing around with ofxFFT and it’s a lot of fun. But I hate being reliant on
1 ) playing a static sound file on my computer
2 ) using my computers microphone

I’m working on a project to collaborate to some DJs and if I use a microphone LIVE there’s the danger it will get blown out fairly easily. What would be the best way tapping into a DJs stream and bring it directly into FFT ? Would it require external hardware ? Would playing music off of itunes or a mobile device ( for testing ) work in a similar way ?

The end goal is to make everything gesture driven but here’s some quick experiments I’ve been doing :
http://vimeo.com/48902155
http://vimeo.com/52211641

My code is up on github @ https://github.com/benMcChesney/VJ-Experiements but it’s still in the very early stages.

Thanks for any feedback !

#2

Hey Ben!

if you’re on a mac you should be able to just plug in an audio cable and set your system sound settings to line in instead of built-in microphone.

Perhaps some mac’s don’t have a line in jack, im not sure which ones, but in that case just get a usb dongle with line in port and do the same thing.

[edit] Cool visuals BTW!

#3

Cool ! Thanks Tim. I’m testing on my OSX laptop for now so I’ll give this a shot.

#4

At the end using the microphone is the easiest way, you just need to scale down the values, because you might run into technical difficulties of getting output from the DJ mixer, because usually there is only one “REC” output (which is the one you want to get sound from).

#5

When I VJ I almost always use an audioline from the DJ’s mixer or from FOH, and usually get it. I normally run it into a bpm-analysis gadget (soundbite micro) which gives me bpm as midi clock, or directly into the laptop, or first into one of our mixer for some signal leveling and distribution to my VJ colleague.
The signal quality is much better that with a direct line, but of course it’s always smart to carry a backup microphone in case something goes wrong (no/wrong adapters, only xlr available, no output free,…).
To head off any potential problem I’d just put the audioline into your techrider. Specify which connector you want, otherwise the sound tech will most probably give you (balanced) XLR, which you can’t use directly. :wink: