Welcome back to a new after effects tutorial, this one isn't going to be very long.
I just want that you guys don't need to buy expensive plugins for after effects to be able to synchronise your animations with any music.
But.. if you need more control of the sound.. then go have a look at Trapcode-Soundkeys for a more accurate soundplugin.

Let's get to work.. Before you start get yourself something to drink, then I promise you, you will be playing with this for hours :))

Ok, enough with the jokes.. ;)
First of all get a nice sound file with some good clear beats, mine isn't really perfect, but I couldn't find any *legal* mp3 to use here. I bet you have something better then this.


Moving on to after effects.. create a new composition with our standard size of 320x240px and a black background, I've used a composition length of 10sec, but you can always change that later on depending on the length of your soundtrack.

Import your sound file into after effects by doing a right-click on the project window or under File -> Import -> File

Sorry for my lack of creativity this time, but I just really want to show you the basics of soundkeys, for that I've created 2 solids and one text layer as you see on the screenshot.


How did I created those?
Easy.. just press CTRL+Y to create a new solid, my both solids have a size of 80x80px and a different colour for each one. Give them also an unique name so you don't mix everything up in case of more then 10 layers.

The text has been created by clicking on the text tool or by pressing CTRL+T. Try to position all the elements nicely on the stage and don't put them too close to each other, otherwise they will be overlayed when the movie plays (depending on your soundtrack)

ok, is everything on the timeline? great! now let's get to the fun part of it :o)



Now let's drag and drop our soundtrack file into the timeline, be sure that your playhead is at 00:00 otherwise the sound will not be placed on the beginning of the movie.


Now right-click your audiolayer and go to "Keyframe Assistant" and "Convert Audio to Keyframes". You will notice that a new layer has been created for you named "Audio Amplitude", it is being displayed as a red square on your composition window, you don't really need to move it away from there, since it will not be visible on the end movie.
If you open the effects dropdown of that layer you will notice 3 different layers inside of it

• left channel


• right channel


• both channels

Inside of each one you will an already animated function parameter called "slider"
Inside there you find a bunch of keyframes, those keyframes are the highs and lows of your soundtrack, going from 0 - 100

Now select the textlayer and press S on your keyboard to open the scale options of that layer.
While you hold the ALT key press the small stopwatch besides the scale option now you will get a new view on your timeline, here a screenshot of my timeline


You've just entered the expression mode of after effects, expressions are similar to javascript or actionscript, Adobe calls them expressions.
The most important function for beginners on expressions and also pro's is the pickwhip tool , try it out, click and hold the pickwhip tool and drag it to the sliderfunction of the "Audio Amplitude" Layer, you will automatically get a script written besides your scale option of the text layer.

Press Enter to confirm the script.

Now press "0" on your numeric keypad, to watch a RAM preview of your movie, and you will see that your text is moving to the beat of the music! :o)

Well that's it, you can control ALL effects and parameters that have a stopwatch besides it with this technique..

On my preview video you see that I've animated the scale and rotation parameters of the text and squares as also manually changed the script so the squares are bigger then the actually sound parameters.
Again! you have to adjust the parameters to your actual project, since sound is always different.
I've wrote an expressions tutorial a while ago, you can still visit here to get a better overview of what are expressions.
EXPRESSIONS TUTORIAL

Here my preview video (you need flash player 8 installed)