The rock world has promised to "crank it up to 11" to mark the death of Jim Marshall, the "Father of Loud", whose groundbreaking amplifiers gave extreme volume to generations of guitar heroes.
Marshall, who died aged 88, devised the stage equipment which first allowed Pete Townshend and Jimi Hendrix to pummel audiences into submission.
The Marshall, arrayed in huge cabinet stacks of loudspeakers, formed the floor-to-ceiling stage backdrop to almost every headbanging, heavy metal act.
Launched in 1965 as a cheap British alternative to American amplifiers, Marshall's breakthrough amp offered guitarists depth and a thunderous, raw power without diluting the sound.
Eric Clapton and Jimmy Page seized upon the simple black box, housing a speaker and volume knob, which Marshall, a drummer with an electrical engineering background, approved for sale after rejecting six prototypes.
The Marshall legend was sealed in the parody film This Is Spinal Tap when guitarist Nigel Tufnel boasted that his volume control extended to 11, or "one louder".
Marshall responded by producing amps which could be turned up to 20.
Slash led the tributes, tweeting: "The news of Jim Marshall passing is deeply saddening. R & R will never be the same w/out him. But, his amps will live on forever!"
Tim Burgess, singer with The Charlatans, urged fans "whatever you're listening to, just turn it up to 11. Make it one louder for Jim".
A September Wembley Arena concert marking the company's 50th anniversary and featuring members of Iron Maiden and Whitesnake, will now be a tribute to Marshall.