Master Compression and Clipping Analysis

In this post I want to analyze clipping and compression by looking at songs that are plotted as a histogram of the normalized amplitudes of the song waveform. Normalized meaning the maximum song waveform value is 1 and the minimum is -1. The x-axis is the amplitude of the audio signal and the y-axis is the number of samples at that amplitude.

Relatively Uncompressed and Unclipped

Before we dive in let's look at a song that is relatively uncompressed and unclipped

Clipping Example 1
Figure 1: Amplitude distribution histogram for Odesza Sun Models

Above is a standard looking song that doesn't appear to have much compression or clipping. Compare this with the images below

Compression and a Little Clipping

Clipping Example 2
Figure 2: Amplitude histogram distribution for Deadmau5 I Remember

This is a histogram of the deadmau5 song "I Remember". You can see the spikes at the top of the histogram, which represent clipping. It also moves out linearly like a pyramid, which I believe implies the linear compression ratio being applied beyond the threshold.

Compression and Heavy Clipping

Clipping Example 3
Figure 3: Amplitude histogram distribution for Skrillex Scary Monsters and Nice Sprites

The image above is a histogram of the skrillex song "Scary Monsters and Nice Sprites". You can see the outsized spikes at the top of the histogram, which represent clipping.