bdp35
04-22-2015, 02:35 PM
I have removed a pair of Heppner horns from my Altec speakers. One is model number 21517-1, and the other is model number 21517-3. The mouth on each measures exactly the same, and both are made out of aluminum (painted black). There are a couple of differences: the 21517-3 has a 1.5" longer throat, and has a Styrofoam silver cap. Other than the obvious visual differences, can someone tell me if they share the same 2,000Hz - 20,000Hz response and produce the same sound characteristics? :confused: I am not sure if I should find another 21517-3 horn (or a Realistic 40-1228 horn), or drop the 21517-1 horn back in the cabinets after I complete my restoration of the speaker cabinets. :dont-know: