Very interesting! I have a few sets of random transformers sitting around and I've been thinking about doing something just like this. Do you have schematics or any any info you could share?
I just wired 1:1 balanced to balanced. No schematics, just followed pinout.
WE has more headroom so wired first from XLR input then goes to UTC.
I'm about to receive some Neumann, Telefunken and Malotke iron and I'm studying some options: - passive transformer stereo box with bypass for each tx - adding API/NEVE/990 drivers with output attenuation for each tx