Low fidelity

Low fidelity or lo fi (adjectival form "low-fidelity" or "lo-fi") is a type of sound recording which contains technical flaws that make the recording sound different compared with the live sound being recorded, such as distortion, hum, background noise, or limited frequency response. The term "low-fidelity" is used in contrast to the audiophile term high fidelity or "hi-fi", which refers to equipment that very accurately reproduces music without harmonic distortion or unwanted frequency emphasis or resonance. The ideas of lo-fi are taken to extremes by the genre or "scene" of no fidelity, or "no-fi". Some lower-budget recordings from the 1970s and 1980s have an unintended "lo-fi" sound because of the limitations of the analog recording and processing techniques of the time, which introduced unwanted artifacts such as distortion, hum and phase problems. In some recordings, however, high fidelity recording is purposely avoided, or the artifacts such as simulated vinyl record crackles are deliberately retained or added in for aesthetic or historical reasons.

Some unique aural qualities are available only with "low-tech" recording methods, such as recording on tape decks, using analog sound processors (e.g., analog compressors or reverb units) or vintage effects units. The lo-fi aesthetic has even contributed to musical subgenres, such as the "lo-fi" subgenre of indie rock and a great deal of punk rock. Lo-fi techniques are espoused by some genres outside the indie rock world, particularly by punk rock, hardcore punk and some heavy metal bands (especially within the sludge, extreme metal and black metal scenes), where the very low-quality of the recording has become a desirable quality, as it is associated with authenticity, as well as a "darker" sound or a "rebellion" against the costly studio production techniques used by successful pop punk or pop metal bands. In punk and hardcore bands of the 1980s, lo-fi sound often occurred because bands did DIY recordings with an inexpensive Portastudio tape deck, rather than using a high-end recording studio and professional audio engineers.

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