How Magnets Influence tone

“This is very important,” says renowned pickup maker Tim Mills. “The two most common magnets used in guitar pickups are Alnico and ceramic. They reproduce very different tones from a guitar when used in a pickup. Alnico, as a general rule, always produces a fuller, warmer tone with pronounced mid-range and sweeter highs. Ceramic, by comparison, produces a much brighter high, smoother mids and tight, fast-tracking bottom-end.”