B&K preamp design questions

[SirPaulGerman]

I was able to pick a nice B&K Pro 10 ( there is a PRO-10mc and also a Pro-10 MC-101 ) the one I got was the 1st version

It sounds amazing, but there zero information out there

There is 2 op amps, and the owner gave me the owners manual

What do you guys make of the design ?

 

[SirPaulGerman]

Here is the B&K Pro 10MC

is very different than the regular pro