A guitarist will use an equalization (EQ) pedal for several reasons.

1. Tone shaping: EQ pedals allow guitarists to adjust the frequency response of their guitar tone by boosting or cutting certain frequencies. This allows them to shape their tone to better fit their individual playing style and musical preferences.

2. Problem solving: EQ pedals can help guitarists fix issues with their tone, such as eliminating harsh frequencies that cause feedback, or boosting frequencies that are too weak.

3. Mixing: When playing live or in the studio, EQ pedals can be used to help a guitar sit better in the mix. For example, a guitarist might cut certain frequencies to avoid clashing with the bass or drums.

4. Versatility: EQ pedals can also be used to switch between different tone settings, making it easy to switch between a bright, aggressive tone for lead playing and a darker, more muted tone for rhythm playing.

An EQ pedal is a versatile and powerful tool for shaping and enhancing a guitarist’s tone, and it can be a valuable addition to any guitar player’s setup.