Well, maybe I need to dig around more in the trunk and see. All I have is wires and the enclosure where the Amp and DSP go is empty. There is no amp in this setup (unfortunately) now. The Xtrons has the treble pushed all the way up. The new 6.5's in the door have no treble but I have a decent amount in the new tweeters. (Trimmed the new 6.5's with tin snips and mounted in the original plastic enclosures with clear silicone). If there is not a passive crossover upstream the only thing I can think of is that the previous owner has the speakers out of phase which is not likely due to the sound quality. I am advanced-beginner skill level with car audio.