Too much hum and buzz in an audio installation? The problem might just be an electrical wiring problem somewhere in the building,
An excellent resource on the subject of Electromagnetic Interference prevention and correction is a book written by Karl Riley, "Tracing EMFs in Building Wiring and Grounding", ELF Magnetic Surveys, 104 Old Farm Rd., Hampstead NC 28443, 1995, 2005, 2nd printing 2007 - highly recommended. It's available from a number of sources in the USA.
A number of Mr. Riley's articles on the same subject are posted at Mike Holt Enterprises.
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