EFFECTS OF ELECTROMAGNETIC INTERFERENCE AND VOLTAGE VARIATIONS IN AMPLIFIED AUDIO SYSTEMS: A BIBLIOGRAPHIC STUDY

This article analyzes the effects of Electromagnetic Interference (EMI) and voltage variations on the operation of amplified audio systems, focusing on low-cost contexts, such as home studios, churches, and school environments. The research is exploratory, qualitative and bibliographic, based on Course Completion Papers, technical standards and specialized literature. The studies by Netto, Pimentel and Kertscher (2017), Montenegro (2020), Filho (2021), Sledz (2021) and the book by Dias, Castilhos and Martin (2019) were examined, in addition to standards from the International Electrotechnical Commission (IEC), International Special Committee on Radio Interference (CISPR), International Telecommunication Union Telecommunication Standardization Sector (ITU-T), Brazilian Association of Technical Standards (ABNT) and documents from the National Telecommunications Agency (ANATEL). The results indicate that EMI and voltage fluctuations significantly compromise the sound quality and durability of equipment, especially when they are low cost and lack adequate protection. Strategies such as electromagnetic shielding, efficient grounding, use of balanced cables, and improvement of Preamplifier circuits proved effective in mitigating the problems. It is concluded that accessible technical practices can raise sound quality in simple systems, contributing to more stable and reliable audio environments.