I have had a pair of ADS 710s that I purchased in the early 80's. Two of the woofers did not work. I also wanted to have the crossover recapped. I saw that a gentleman from Arizona who was an engineer for ADS still does repairs. I sent all four woofers and the crossovers to him. He rebuilt all four speakers and they look like brand new speakers. After placing them back in the enclosures I was very impressed with the sound. I would highly recommend Richard for all your ADS needs.