Perfect condition. Comes with RTA mic and mic bag. $250 shipped. The DriveRack PX Powered Speaker Optimizer has everything you need to get the most out of your stereo powered speaker system. It even includes stereo or mono subwoofer support. With the included dbx M2 measurement mic, Auto-EQ corrects for audible deficiencies in the room environment. Our patented Advanced Feedback Suppression (AFS) kills nasty feedback, allowing problem-free operation at higher sound levels, while our patented Subharmonic Synthesizer extends bass response for enhanced bottom end. With all that, you also get classic dbx compression and the protection offered by our graceful PeakPlus limiting. Your ears, your audience, and your powered speakers will forever thank you.