My speakers are highly efficient horn tweeters and horn midrange from Electrovoice in 1958, came from my uncle's Fisher President II Console.
I changed the tweeters from T35 to T350's, and use the L-Pads to match their volume to the Mid Horn.
https://www.audiogon.com/systems/11420
both horns have drivers with impregnated linen, I'm told essentially indestructible. I have re-coned the 15" woofers a few times over the years, I am shocked and deliriously happy that the horns are still producing (I blend them with the woofers using a pair of L-Pads and an SPL mic on a tripod at ear level with test tones) I did melt a T-35 tweeter coil blasting Inna-Gadda-Da-Vida on Reel to Reel Tape once.
I guess they are over 100db efficient, maybe 102, 104 ?????
You are correct, If I get my ear near the tweeter, I might hear some hiss, but often not.




