Originally Posted by
MUSICCITY
I just want to say thank you in advance for taking the time to read this and potentially steer me the right direction. I am a fan of vintage Altec, JBL, and Infinity and recently purchased a large number of vintage Altec pieces including several 1003B and 203B Horns. I also received 9 large 20 pound compression drivers in the deal. One of them is marked a 291-16a. However the original owner believed several of them to be 288's and probably C's. The problem is 8 of them have no stickers. All of the drivers appear virtually the same to me. I notice that a few of them have the bug/dust screen deep in the canal and several of them have the screen on the outer part of the canal at the gasket. Off hand that is the only difference I see among them.
Can anybody please tell me how to distinguish a 291-16a from a 288c or any of the other 288 drivers? I have looked up PDFs and have found two types of 291-16a drivers but no PDFs on the 288s. I greatly appreciate your time as I don't imagine I am the first to wonder how to determine the model number of a driver missing its sticker.
One neat note. I opened them up to check, and it turned out to be true. Each one of the drivers has an original 299 diaphragm with the Altec logo printed on the dome. He said that the place that used them originally chose to use those 16 ohm diaphragms. Thank you again so much!
One last note. I tried to upload some photos but they would not post. I kept getting a red exclamation point. I am new here so I will read up on what is wrong. In the meanwhile, I can email photos for reference if anyone wants.