- Distortion is due to non-linearity
- Harmonic distortion is where integer multiples of the input frequency occur
- Intermodulation distortion is where two signal components multiply together to make new ones
- Every amplifier has some non-linearity; good design and operation within the intended power input (drive) / output range, i.e., not overdriving it minimises distortion
- Distortion manifests itself as interference and splatter