I really have no interest in the motor and our customer will get to keep it. I was going to try and rebuild it for fun because it really has some issues and there seems to be a lot interest for some odd reason, but the bottom line is, only 25 exist, and for a good reasons. The magnet ID is large, the Bl is small, and the flux modulation was really amplified with our higher excursion top assembly which is why it didn’t work so hot. The MT recones’s worked better because the gap was shorter and the magnets ID was smaller, and there was a lot more Bl so there was more saturation to make up for the flux modulation caused from the voice coil. Secondly the voice coil was a lot smaller (in height and in width) in the MT so there was weaker magnetic field generated from it which aided in favor of less flux modulation.
On the other hand, the Destroyer had no hope. With our huge coil and even less magnets and a larger gap plate, there was no saturation, less magnetic field from the magnets, and a larger coil. The flux modulation was beyond hope, and it really made for some nasty distortion at a particular frequency at a particular voltage. The very limiting 8 or 8.5" spiders originally on the destroyer with the wide 4" vc actually worked to this motors advantage in a very unpredicted way. The very stiff compliance and low mechanical excursion limits helped prevent the coil from doing its dynamic shifting, not the way it should be designed, but for 25 units, it got the job done. I was going to bake the motor at 1000 degrees to demagnetize it, then rebuild it with copper to demonstrate this, but its not worth my time because I think its clear now what the issue was.
Evan is getting an new 18” 4HP for 600 off and he gets to keep his old speaker. Or he can get his 200 back and keep the speaker too.
I think this thread is over.
Thank you.