U67 de-emphasis network

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What I am talking about is quite obvious when listening to this comparison by the reseller of Ruud's circuit (Vintage U67 vs. Ruud67 ;)) - knowing the Ruud67 is equipped with a chinese K67 in this case and might sound different with a proper capsule (I am using Arienne's K87):

The difference made by the microphone capsule is more obvious than any other accessory. I found that there are differences between many of Neumann's original K67s, but they are far less obvious than other capsules. Perhaps these subtle differences I hear are the result of natural aging over the years.
 
Guys, doesn't the dynamic/harmonic behaviour of the BV12 transformer's primary : tertiary "translation" also factor in when tapping the signal there for NFB re-injection? Apart from the questions considered here regarding the role of the capsule itself.

I found myself using my 67-ish mics following RuudNL's alternative schematics with great results in situations, where a vintage U67 would sound a tad bit too pre-compressed for me (e.g. classical Grand Piano). Ruud used a usual transformer and taps the NFB signal directly after the coupling capacitor:
https://groupdiy.com/threads/u67-ish-microphone.75162/

Maybe there are other reasons, why those "alternative" 67ish mics sound less compressed (which of course can be a good or bad thing, depending on what you're after), but I am wondering, how the tertiary winding might play a role in this?!

I would naively think that negative feedback from the tertiary transformer winding would tend to make the transformer more transparent in normal uses; whatever color the transformer might tend to add to the output on its own, the negative feedback would tend to cancel it out. (Isn't that the point?)

But if that's true, why bother with transformer-coupled output and more expensive transformers with tertiary windings?

What am I missing?
 
What I am talking about is quite obvious when listening to this comparison by the reseller of Ruud's circuit (Vintage U67 vs. Ruud67 ;)) - knowing the Ruud67 is equipped with a chinese K67 in this case and might sound different with a proper capsule (I am using Arienne's K87):

wouldnt trust mic and mods comparisons. their u87 one is just the same file with compression
 
wouldnt trust mic and mods comparisons. their u87 one is just the same file with compression
Sure, I don't trust them, either, but this comparison sounds pretty much the way I have experienced both mics to sound like, at least with vocals in close proximity. So please let's not discuss M&M and their policies any further as in so many other threads - I didn't intend to open this can of worms again.
 
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