Melodic hardcore is broadly defined, however generally incorporates fast rhythms, melodic and often distorted guitar riffs, and vocal styles tending towards shouting and screaming. Many notable bands, such as Dag Nasty and Lifetime use minor interval chords on guitar, such as minor ninth and seventh chords, as well as fifth or ninth harmonies on vocals. Many groups also drop tune their instruments. Tempos commonly range from 180 to 210 beats per minute, with very few bands ranging outside of a 4/4 time signature.