Glass tombs

An electrical fuse is a thin, underrated piece of wire, encased in a glass or ceramic tomb, that vaporizes when its electrical ratings are exceeded. Fuses were once common in homes, but are rare today–replaced by magnetic circuit breakers instead. But fuses are still used in nearly all home electrical equipment and appliances, including many stereo and some loudspeaker designs. The fuse has a long history. The first introduction of this protection device was in 1847, when Louis-François-Clement Breguet, a French physicist and watchmaker, recommended the use of thin wires to protect telegraph stations from lightning strikes by melting the smaller wires and disconnecting the telegraph stations from their battery power sources. This protection technique came to be known as a "fuse" from the French fusée which means, "spindle" (they sort of look like spindles). Fuses have a number of advantages over circuit breakers. They are far less expensive, easily replaceable, typically faster, and not prone to failure. Almost all audio equipment, from the most expensive amplifiers to the lowest cost DACs and CD players, use fuses and not circuit breakers. Fuses are effective, fast and ultra reliable means of protecting sensitive circuitry from failure. But in higher end, higher resolving audio equipment, people feel strongly they affect sound quality. So, the first question we should all be asking: is it true? And if so, the second question should be, why? Let's tackle the first. Yes. In my experience, fuses matter. My first run in with a power line fuse impacting sound quality came courtesy of our German distributor, Jurgen Sachweh. Jurgen had been visiting us, perhaps 5 years ago (and before the IRS system in Music Room One), and asked if I wanted to hear something unusual. Of course I agreed. Jurgen said he needed some time to set things up and grabbed one of our engineers to help. Later that afternoon he drug me into Music Room One which, at that time, had the Maggie system with Descent subwoofers and Tympani 1D bass panels (a rather sweet and revealing setup). We played the PerfectWave DAC directly into a Classic 250 power amplifier and all sounded well. We stopped the play, Jurgen demanded I keep eyes forward so I wouldn't know what he was doing, and proceeded to replace the power fuse in the PWD. Immediately I heard more details, depth, openness, and soundstage width. It was as if a thin veil of acoustic gauze had been removed from the Maggies. Wow. I still had no idea what he was up to and asked him to undo whatever it was he had done. After a brief redo the layer of gauze was back. We probably did that experiment two or three more times–the results were identical. I could stand it no longer and demanded to know what the hell he was doing. The answer shocked me (not to make a pun). Turns out his friend owned Audio Tuning, a manufacturer of high end fuses and we were sampling their wares. Tomorrow we continue.