When experimenting with video effects on Adobe After Effects I discovered the

audio spectrum application. This is where a range of lines move up and down in

accordance with a selected audio track. I want to use this in my music video to

further the conceptual, visual effects theme and also because the house music

genre of Static (get out my house) is, by nature, quite loud and ‘bassy’. So this audio

spectrum can accentuate these aspects of the song. I planned to create this effect

to lay over the footage in my music video. (Note: numbers in square brackets make reference to points on the images outside of this document)

To begin the process of creating this audio spectrum I created a new composition in

After Effects, imported my music track and added a solid layer to the timeline. The

solid layer will become the audio spectrum, leaving a blank alpha channel in the

background which will allow the effect to be placed over the footage in my music

video in Premiere Pro. To apply the audio spectrum effect to the solid layer I clicked

on (when the layer is selected) Effect > Generate > Audio Spectrum. This then

opens Effect Controls window where the audio spectrum can be manipulated (I also

used the Audio Waveform which is based on the same principles).

To link the audio spectrum to the track I was able to select Static (edited version) in

the Audio Layer drop down menu [1]. This linked the movement of the audio lines to

the sound levels in the song.

I was then able to adjust the preferences of the audio spectrum for instance, the size

and placement of the spectrum by changing the Start/End Points and Frequency [2];

the quantity of the lines by changing the Frequency Bands [3]; as well as the height,

colour, thickness and so on [4]. Experimenting with these preferences created a

range of interesting different spectrums.

To create a circular audio spectrum I went to Effects and Presets, searched Polar

Coordinates and dragged the effect onto the layer. This results in the polar

coordinates controls appearing in the effect controls window [5]. Here I am able to

change the interpolation to 100% and the type of conversion to ‘Rect to Polar’. This

control, alongside changing the Start Point to -370,360 and End Point to 2000,360,

created my circular audio spectrum.

Once I was satisfied with the preferences that I had set on the audio spectrums, I

needed to render and export the effects. To make sure that the alpha channels

remained I changed the Video Output > Channels to RGB + Alpha. This means that

the clip’s background will remain opaque and will be able to be placed over other

footage.

Due to the fact that many effects in After Effects, particularly audio spectrum,

produce such large files, my audio spectrum clips were multiple gigabytes, even

though they were only 10-15 seconds. This meant that, when put into Premiere Pro,

the program became very slow and the video clips lagged when played. To resolve

this issue I used Adobe Media Encoder. This is an incredibly simple file reformatting

program which, once I had dragged and dropped my rendered video files, allowed

me to change the format (from .avi to .flv) of the clips as well as the presets (encode

alpha channel) [6].

After the encoding had finished the results of this quick process proved extremely

helpful. The size of the files had dramatically decreased (the largest reduced from

6.7GB to 10MB) and the clips played much smoother in Premiere Pro.