Probably going to build some offset kickpanels for my E36 BMW sedan. What would the best approach and materials to use for sound deadening the cavity behind the speakers?

Thanks in advance,

I believe PLOW built some kick panel enclosures for his E46, you may want to PM him. Personally I'm going with the doors and an underdash arrangement on my E46.

Mark

He he....I just cut the entire kick panels out of my car. NO rattles now!

But seriously, I would focus on solidly mounted MDF baffles, and then put a Deflex pad (from Cascade Audio Engineering) behind each driver.

I am not sure I understand what you mean by MDF baffles? I was thinking of making the offset mounting part out of MDf and fibreglass. Would it be of any use to treat the internal metal with a brush on sound deadener?