Dave, I'm experiencing some audible distortion from the dustcap on my DMX. The DC isn't supported in the middle and at higher frequencies it makes an annoying popping sound. I'm wondering how I can rectify that, would you suggest getting a thin foam sheet and attaching it to the dustcap to dampen it? Felt circles? The fuzzy part of Velcro?
At low frequencies it's awesome, it moves the car quite nicely, I didn't discover the popping/slapping sound until I played "Time" by Pink Floyd. If you're familiar with the song the sound kicks in after the chimes stop and the bass line starts. I've run into it with some kick drums too.
I'm trying to come up with a solution that won't involve me pulling the sub. I'm asking you because of your background with making subs and all. I think the DC is distorting due to it resonating at higher frequencies so I'm thinking that damping material will be the best bet but I don't want to add a bunch of weight to the cone either.
Any options you can come up with would be much appreciated.