Micromega DUO DAC D/A Converter - how many Versions on the Market? - Overview wanted

[tiefbassuebertr]

Until now I thought that there were only two versions in a small outline: "BS" and "BS2" (BS means bit stream)
But obviously there were additional versions, like this version with integrated pre-amplifier (i.e. including volume control and source select resp. input selector for two inputs) - go to
https://pinkfishmedia.net/forum/threads/early-micromega-duo-dac.254337/
This version I had never seen before. Unfortunately there is no image with sticker for reading the exact model naming.

Under
https://vasiltech.narod.ru/CD-Player-DAC-Transport.htm
is mentioned the version "BSY".
On the web I don't find any information concerning this version.

And by chance I discover in the normal outline the versions "PRO" and "PRO2".
Who have an exact overview of the whole DUO series from Micromega ?

 

[tiefbassuebertr]

Images DUO BS - maybe all BS versions equipped with SAA7220 (but I don't know exactly).

 

[VT-52]

Blast from the past. This was the first ever high-end CD player/dac I listened to. I still have the Duo drive (Duo CD3) and an older one (can't remember the number) with darker acrylic cover (Solo).

 

[tiefbassuebertr]

BS2 versions; whether the BS2 version is equipped only with the Yamaha input receiver IC YM3623B or also with CS8412 - I don't no.