Definitive Technology no longer has replacement drivers for my speakers and I did a lot of research trying to find a suitable replacement. My right tower had a dead 15 and I had lived with it for 6 months since I run transducers in the furniture and an 18" subwoofer in the living room. I was going to buy a pair originally to save on shipping, but I figured I would experiment with the lowest expense. I installed the Mavin within hours of its arrival and was astounded. I have enjoyed my Def Techs for years and am sure I will enjoy them for another decade. The difference that the 15" Mavin made was enough that I am considering removing my 18" subwoofer while I am renovating living room. It was an excellent replacement for the enclosure and I ordered the second replacement today because I enjoyed the change so much. The cost and the specs of the driver have delighted me more than christmas morning. This is the perfect replacement for anyone that has BP2000s and I couldn't possibly recommend it more.