Jim Marshall, whose guitar amplifiers were used by some of the biggest names in rock, has died aged 88.
A statement on his company's website paid tribute to the man called "the Father of loud".
It said: "It is with profound sorrow that we announce the passing of our beloved founder and leader for the past 50 years, Jim Marshall. While mourning the Guv'nor though, we also salute a legendary man who led a full and truly remarkable life."
It went on: "While the entire Marshall Amplification family mourns Jim's passing and will miss him tremendously, we all feel richer for having known him and are happy in the knowledge that he is now in a much better place which has just got a whole lot louder."
Mr Marshall, from London, worked as an engineer and a drummer before he started building amplifiers in his garage.
He went on to open the first Marshall factory in 1964 and soon his amplifiers were the equipment of choice for names such as Jimi Hendrix and Pete Townshend.
Former Guns N' Roses guitarist Slash said the news was "deeply saddening".
He told followers on Twitter: "R & R will never be the same w/out him. But, his amps will live on FOREVER!"
Mr Marshall was given the OBE in 2003 for his services to music and charity and donated millions of pounds to good causes including the Royal National Orthopaedic Hospital in Stanmore where he was treated for tuberculosis as a child.
He is survived by two children and two step-children.