Yeah dont think there mic pre circuits would sound as good as the usual BA redd v72 circuits so could use bits for those, yeah I like the panels would make Altec 438A tho ...one EMI has 600 Ohm out put socket...followed it back to a U pad 4x 150 ohm & a transformer.... tried it very quickly connected to a redd diy pre I have & sounds as good as my Sowter I usually use for redd
I have a mystery part its cylindrical same size weight its as say mic transformer only 2 connections with little drawing of a coil on it .....maybe a inductor oh & it plugs into a socket
Many thanks