Working With Audio

There are a few points to consider when working with sound in AE...

Digital audio files describe this analog sound by taking snapshots. Each snapshot is described by a specific length of digital code and that length is defined by the bit depth. Files that are saved with higher bit depth can describe more subtlety and nuance. Consider the difference between calling something Red and calling something Candy Apple Red.

Sample Rate is a measurement of how many times a second the sound wave was recorded (sampled). Higher rates provide more snapshots per second and hence a higher fidelity playback. The lower the sample rate, the lower the fidelity, with slower rates introducing distortion, called digital artifacts.

Digital files with higher bit depth and higher sampling rate are larger than the same sound embedded at a lower fidelity. Audio CDs use a sample rate of 44.1k (44,100 cycles per second) at 16 bits, while mulitmedia DVDs typically use a smaller file size of 22k. Web audio is frequently stored at a noisy 8 bit. Stereo files are (not surprisingly) exactly twice the file size of mono files. It is important to experiment with the audio settings found in the Render dialog box to see the best balance of file quality and file size.