The component chart in the following Altec catalogue lists the A9 system with a 511D horn. Misprint or is there such a model?
http://www.pearl-hifi.com/06_Lit_Arc...he_Theater.pdf
Also, the Model 830A Laguna used a 511C horn. Any unique design features?
Altec Lansing Laguna 830A Vintage Speaker Matched Pair Very Good Cosmetic and Working Condition Photo #1157111 - US Audio Mart
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