Equalisers, or EQs, are tools used in recording studios to adjust the frequency response of an audio signal. EQs are typically used to cut or boost certain frequencies, allowing the engineer to shape the overall sound of a recording. The frequency bands that an EQ can adjust can vary, but most common EQs feature a low-frequency band, a mid-frequency band, and a high-frequency band. The engineer can adjust the gain of each band to either cut or boost specific frequency ranges in the audio signal.
Equalisers can be used for a variety of purposes in the recording process. For example, a high-pass filter can be used to remove low-frequency rumble or noise, while a low-pass filter can be used to remove high-frequency hiss or unwanted harmonics. EQs can also be used to correct problems in the recording, such as excessive resonance or harshness in a particular frequency range. Additionally, EQs can be used creatively to shape the tone of a recording, such as boosting the bass for a heavier sound or cutting the mids for a more “scooped” sound. EQs are a crucial tool in the mixing process and can greatly affect the final sound of a recording.
Parametric equalisers, or parametric EQs, are a type of equaliser commonly used in recording studios. Unlike standard graphic EQs, which feature fixed frequency bands that can only be adjusted in level, parametric EQs allow the user to adjust the center frequency, bandwidth, and gain of each band independently. This provides the engineer with more precise control over the frequency response of the audio signal, allowing them to make very specific adjustments to the sound.
Parametric EQs are often used for more advanced equalisation tasks, such as surgical correction of resonant frequencies, precise tonal shaping of instruments, or adding emphasis to certain frequency ranges in a mix. The adjustable bandwidth, or “Q” factor, of each band also allows for more precise control over how much surrounding frequencies are affected by the EQ. Parametric EQs can be used for a variety of instruments and applications, including vocals, drums, guitars, and mastering. With their precise control and versatility, parametric EQs are a powerful tool for recording engineers and mixers, allowing them to fine-tune the sound of a recording with great accuracy.