Can anyone tell me if there is an after market woofer that I can replace the factory installed woofer that came with the 97 LS400 Nak system? I am interested in something with the exact fit that won't require too much of a hassle to install.

Thanks

 

You need to look for a free air sub woofer. I forgot who makes them but ask around in stores for a free air sub woofer.

 

JL IB4 will work as well as any of Image Dynamics subs.