Fuzz bass is a style of playing the electric bass or modifying its signal that produces a buzzy, distorted, overdriven sound, as the name implies. Overdriving a bass signal significantly changes the timbre, adds higher overtones (harmonics), increases the sustain, and, if the gain is turned up high enough, creates a "breaking up" sound characterized by a growling, buzzy tone. One of the earliest examples may be the 1961 Marty Robbins Country and Western song "Don't Worry." By the mid- to late-1960s, a number of bands began to list "fuzz bass" in addition to "electric bass" on their album credits. Two well-known examples are the Beatles' 1965 song "Think for Yourself" (from Rubber Soul), which marked the first instance of a bass guitar being recorded through a distortion unit, and the 1966 Rolling Stones song "Under My Thumb". Album or performance credits for fuzz bass can be found from every decade since then (see examples below). Fuzz bass can be produced by overloading a bass amp's tube or transistor preamplifier, by using a bass fuzz or bass overdrive effect pedal, or for the most powerful effect, by combining both approaches. In the 1960s and early 1970s fuzz bass was associated with the psychedelic music (e.g., Edgar Broughton Band), progressive rock (e.g., Genesis), and psychedelic soul/funk (e.g., Sly and the Family Stone) styles, and it tended to be a "warmer", "smoother", and "softer" overdrive-type sound caused by soft, symmetrical clipping of the audio signal that "round[ed] off the signal peaks rather than razor-slicing" them and filtered out the harsher high harmonics. In the 1980s and 1990s, overdriven bass tended to be associated with hardcore punk (e.g., Stormtroopers of Death), death metal (e.g., Mortician), grindcore (e.g., Napalm Death) and Industrial bands (e.g., Ministry), and the tone tended to be heavier, more metallic and more grinding. This is achieved by hard clipping of the bass signal, which leaves in "harsher high harmonics that can result in sounds that are heard as jagged and spiky.