Hey, I've been running a 12" Eclipse Ti off an Orion 1200D for a few weeks now with no problems. Today I noticed this very distinct metallic pinging/rattling noise coming from the sub. Actually to be honest I don't know how long it's been happening, cause I just happen to put my seat down today and heard the noise.
I turned the gain all the way down, bypassed the DSP on the deck (Kenwood XXV-01D) and played some test tones. I set the volume at 25/35 and the noise was there from 20Hz-32Hz. At 26/35 it was audible to 35Hz, and so on.
Then I played some regular bass tracks and again it seemed to surface at lower frequencies. When I played the music the volume was at 20/35 and the sub was barely moving, but I could still hear the noise...
I checked the box (1.25 ft^3 sealed) and the hole where the wire comes out wasn't really sealed...fixed that and it still makes the noise. Pulled the sub out and checked the resistance on each coil, read 3.1 Ohms...they're supposed to be 4. What does this mean?