Hi everybody. I'm new to this board, though I have been to the Great Plains site many times in the past. I'm hoping that someone here can help me. I have a pair of Altec Lansing Model 512 speakers that I purchased in 1994. These were manufactured in Milford PA and were the top of the line consumer speakers at the time. They have built in amplifiers in each cabinet and weigh approximately 120 lbs each. I'm trying to find schematics for the amplifiers, but so far no luck. I contacted the new Altec Lansing Vintage and they said that there had been a fire in the mid to late 90's that destroyed the archives so they don't have them. My only hope is boards like this one or a servicer that would have an old service manual. When they are working they sound great, but one of them is dead right now.