One thing has stayed consistent throughout John Petrucci's long and successful career: the DiMarzio pickups in his guitars. John has been pushing the envelope of progressive metal since the late eighties, and the DiMarzio LiquiFire Neck Model resulted from DiMarzio'smost recent collaboration with John. He used it throughout Dream Theater's tenth studio album, "Black Clouds & Silver Linings". John swears this is the best live and studio sound he has ever had. He wanted a neck pickup with a flowing, singing solo tone when used with a heavily overdriven amp and a clear chord sound with a clean amp setting.
The sound John likes in the neck position of his 6-string translates very well to the 7-string, with fat highs and clean lows for smooth solos and tight bass lines. The LiquiFire 7 isn't an exact duplicate of the 6-string version. The attack is a little more focused and the voicing is shifted down about 500Hz to bring out the sound of the seventh string.
Recommended for neck position. Combine with the DP708 Crunch Lab pickup for the ultimate 7-string pickup set.