I just installed an 8 inch DLS 0A8 subwoofer. I'm loving how good it sounds. When I first got my 2001 Ultra 3 years ago the subwoofer needed to be replaced so I installed a Diamond dual coil 4 ohm. I assumed 4 ohms was correct because the woofer that it replaced was 4 ohms. The system never sounded very good and the bass sounded like crap. After digging though the numerous subwoofer posts on this great site I finally found that the factory woofer is 12 ohms which explains why the system clipped with the 4 ohm woofer. The 0A8 is meant for a free air enclosure and is 8 ohms. Now that I've fixed my blown MLS amp and replaced the subwoofer I'm loving driving my car again. I'm sure it can't come close to the bass of installing a box but I like my trunk space and I'm very satisfied with it now.

 

Your Diamond dual coil 4ohm sub could be be wired in 3 configurations:
Series: 8 ohms
Parallel: 2 ohms
single coil: 4 ohms

More likely the Diamond didn't sound good because the Qts was a lot below 0.7

 

Where did you buy this subwoofer from?

 

You can call the distributor for a local dealer near you. Demo'ing would be recommended too.

http://www.dls.se/en/car/us_retailers.html

DLS America Inc.
Atlantic Towers
18100 Atlantic Blvd. #510
Sunny Isles Beach, Florida 33160
Phone: +1 305-933-5255
Fax: +1 305-933-5244
Cell: +1 786-210-2262

 

i got a 15 inch sub in a sleghammer box about 150 lbs : 1000 watt amp.. it cooks the doors are my next project..i need help with that like to have more power to the doors