To view an audio spectrum, you first need to convert the audio signal into a frequency domain representation. This is typically done using a Fast Fourier Transform (FFT). The resulting spectrum shows the amplitude of different frequencies present in the audio signal. Here’s a step-by-step guide:

1. Acquire the Audio Signal: Start with an audio file or a live audio input.

2. Apply FFT: Use an FFT algorithm to transform the time-domain audio signal into the frequency domain.

3. Plot the Spectrum: Display the frequency on the x-axis and the amplitude on the y-axis. The spectrum will show peaks corresponding to the frequencies with higher amplitude.

The reason for this process lies in the nature of audio signals. Audio signals are composed of various frequencies, and the human ear perceives these frequencies as different pitches. By visualizing the spectrum, you can analyze the frequency content of the audio, which is crucial for tasks like audio processing, equalization, and sound design. According to a study by Karpowicz et al. (2012), visualizing audio spectra can significantly aid in understanding and manipulating audio signals for various applications in audio engineering and music production.