Hobby is finding and restoring vintage stereo equipment from the 70s and 80s. Searched for ADS speakers and your site popped up. Had pair of ADS L300 mounted in the rear of my beloved Datsun 280z for 12 years. Loved those speakers. Apparently the C version of the speakers had foam surrounds and are likely shot. Have had luck replacing foam on other speakers, so it's not a big hurdle.