DiMarzio DP706 D Sonic 7 7-Strings Bridge Pick Up (Black With Nickle)Clarity, warm tone, and high output are the qualities that define the D Sonic. John Petrucci agrees. He's had a lot of experience playing the D Sonic on his 6 string guitars, so when he wanted the same sound from his 7 string we couldn't say no. The D Sonic combination of clean and heavy that works so well with high gain amps for both chords and soloing makes a great choice for a 7 string bridge pickup. The high strings sing and the low strings growl.