April 5, 2012.   Jim Marshall, the pioneering amplifier designer and builder whose innovations and reputation led to his being dubbed “The Father of Loud,” has died. He was 88.

Along with Leo Fender, Les Paul, and Seth Lover of Gibson, Jim Marshall was one of the founding fathers of  modern music equipment. Introduced during the middle1960s, the Marshal amplifier stack revolutionized live performance, providing the decibel power and glory that has driven rock concerts ever since.

Marshall Amplification was established in 1962. It took Jim six attempts to create an amp he was happy with, creating what became known as "the Marshall sound." It revolutionized music. Soon after production began, musicians, including Jimi Hendrix, Eric Clapton and Jimmy Page, became believers. The "Marshall stack," a wall of  black, vinyl-clad cabinets, one atop the other, was seen as the physical embodiment of rock's power, majesty and excess.

As a result, Marshall amplifiers have become deeply embedded in our cultural consciousness. It is a measure of just  how much so that when, in the classic “mockumentary” This Is Spinal Tap, an amp’s volume control is dialed-up to “11” from the standard, ear-splitting “10.” We know it’s a Marshall and get the joke.

Marshall amps delivered the rough and rowdy sound that rockers sought. On Twitter, Mötley Crüe’s bassist, Nikki Sixx, said Mr. Marshall had been “responsible for some of the greatest audio moments in music’s history — and 50% responsible for all our hearing loss.”

One of Marshall’s biggest breaks came in 1967 when Jimi Hendrix visited his showroom. At the time, Mr. Marshall recalled, he thought the guitarist was “just another American chap wanting things for free.” Hendrix assured him that he intended to pay, and ultimately bought four complete stage setups. “Are You Experienced?” Hendrix’s debut album, was released shortly thereafter.

“He was our greatest ambassador, without a doubt,” said Mr. Marshall, who considered Hendrix the best guitarist ever.

But an ambassador needs a strong portfolio. With Marshall Amps, Hendrix was the greatest diplomat rock music had ever seen, the Marshall Sound his calling card.

Marshall was the Sound Heard Round The World.