Rounding out the new Brit series of amps is a preamp model based on the Marshall JMP-1 valve preamp. The JMP-1 was Marshall’s first foray into the world of MIDI control with Marshall tone. It allows players to sculpt the tones they want, then save those tone presets for recall by MIDI control at any time. It's one of the most simple preamps, very straight forward. It has the staple Marshall controls like Volume, Gain, Bass, Middle, Treble and Presence. It features a bass shift, 2 overdrive channels, and 2 clean channels. For its ease of use and its “ready to go” sound character, it quickly became one of the most iconic Guitar preamps of the era. Almost 90% of the pro players at the time had a JMP-1 in their rack of toys.
He pronounced the piece "the guitar I've always been waiting for" and began playing the instrument exclusively. It came to be called Lightning Bolt. Garcia met with Cripe briefly backstage at a Florida concert and commissioned a second guitar for $6,500, known as Top Hat, although Garcia almost never played it. Cripe, whose hobby was making fireworks, died in May 1996 when his work shed blew up. He used an exploding firecracker as the insignia on his guitars' headstocks.