This is a picture of the rack John used for the 2002 World Tourbulence tour. Among the various units there's a DBX 166A (eighth from top to bottom). Confirmation of this being John's rack can be found in [this diagram from *Guitar Geek*](http://www.guitargeek.com/john-petrucci-dream-theater-guitar-rig-and-gear-setup-2002/) and [at :15s in this video](http://youtu.be/4yUUCRJGdko).more
With an Equipboard account you can rate this item, add it to your collection, submit a review to discuss what you like and dislike about it, and associate DBX 166A Dynamics Processor to artists that use it. Create an account!