In contrast , most guitar amplifiers provide tonal coloration and overdrive or distortion of various types .
Audio amplifiers generally are intended to accurately reproduce the source signal without adding unwanted tonal coloration ( i.e. , they have a flat frequency response ) or unwanted distortion .
Most guitar amplifiers provide tonal coloration and overdrive or distortion of various types .
Audio amplifiers generally are intended to accurately reproduce the source signal without adding unwanted tonal coloration ( i.e. , they have a flat frequency response ) or unwanted distortion .