Wow, interesting!
First of all, you should be sure to send him a whole lot of love from us : D
I have a few things I'm curious about - though I don't expect an answer to all of them, heh:
1. Gerhard Narholz is known to be a composer, arranger and conductor, but does he play any instruments himself - and has he played on any recordings, for Sonoton, Intersound or otherwise?
2. Long-time Sonoton mastering engineer Wolfgang Meyscheider has worked on a considerable part of Sonoton's material until c. 2017/2018. Is he still alive, perhaps retired?
3. A lot of Sonoton's now-iconic album art was apparently photographed by Narholz himself. Was this out of pure necessity or is he into photography?
The photography/cover art is often credited to "Intersound" - did they ever serve as an "image library" à la Getty Images/Shutterstock?
4. Narholz is maybe the most prolific user of pseudonyms in German library.
Sonoton has to my knowledge, curiously, not really acknowledged he's behind names like "Sammy Burdson" and "John Epping", so I'm not sure if he'll even want to talk about it - but I've always wondered how it all came about; why does he use so many pseudonyms, and is there any backstory to how the names themselves came about?
I recently learned his middle name is likely Otto, which is how "Otto Sieben" ('eight seven') came about.
- Also, specifically, why was he and Bert Obermair "Paul Prennessel" and "Paul Prennessel"?
I'll let you know if I can think of any more.