811 Fins

[bfish]

...Just what function do the fins serve on the 811 (and 511) horn?

Perhaps they were intended to stiffen the structure...

I think there might be other reasons: styling and product differentiation... Perhaps the fins were intended to differentiate the look of the Altec product from the RCA horns, which did not use fins...

Another reason may have been to maintain a visual continuity with the earlier Altec horns. Altec Lansing had produced only multicellular horns until the introduction of the H-811, and the fins served to visually divide the mouth area, providing an evolutionary appearance change rather than a revolutionary one.

I guess Western Electric must have never gotten that memo.

"The horn is sectoral in form and integrally cast partitions are provided to reduce reflection effects within the sound passage."




courtesy HiFilit.com

I don't know the production dates of the pictured KS series, but W.E. did have fins in sectoral horns that pre-dated the 811.