I picked up these horns the other night.They are 511E's one had a original box the other did NOT but there is some subtle differences.One horn has 2 mounting rings the other just 1,One has the stabilizing fin in the middle of the horn the other does NOT.There was another tag found in the box of a 511E with a ink stamp date code of 9/1/82 picture taken hand written 511E it says on it and different serial # than the box,but horns have no tags.Took small samples of the coating both have Aquaplas on them.But one is quite thick the other not as thick.Rough throats as Steve Mac has noted with his.One of the driver mounting flanges was definitely from a small format driver that I think they may have just reused.I think there is maybe some quality control issue/cost cutting?? Both horns are well damped though from the knuckle rap (No Ring) but obviously the thicker one a little more so.And the throat on the one horn is a little longer than the other 1/2" inch.And color is slightly differnt two different shades of gray.Any thought would be appreciated.Thanks !!!


Altec 511E's - a set on Flickr