Audio and signal transformers are electrical components that transfer power from one circuit to another through inductive coupling. They are commonly used to match different impedances and isolate circuits from one another. This is especially useful in audio and signal processing, as different devices often have incompatible impedances that can be matched with a transformer. Additionally, transformers can help reduce ground loop noise, provide galvanic isolation, and help regulate voltage levels. They consist of an iron core that the two windings are wrapped around. Power is then transferred between the primary and secondary winding in a way that preserves the signal integrity.