In audio engineering, a frequency analyzer is a tool used to visualize and analyze the frequency content of an audio signal. A frequency analyzer typically displays a graph of the frequency spectrum of an audio signal, with the x-axis representing frequency and the y-axis representing amplitude.

By analyzing the frequency content of an audio signal, engineers can identify and correct problems in the mix, such as frequency imbalances or excessive noise. They can also use frequency analysis to identify specific frequency ranges that need to be boosted or cut using equalization (EQ) to shape the sound.

Frequency analyzers are available as both hardware and software tools. Hardware frequency analyzers may be standalone devices or built into audio interfaces or mixing consoles. Software frequency analyzers can be used as plugins in digital audio workstations (DAWs) and may provide additional features such as real-time analysis and spectrum visualization.

Overall, frequency analyzers are an important tool in audio engineering that can help engineers identify and correct problems in a mix, as well as shape the tonal balance of an audio recording.