Also the East Germany-made (in mid 50s) archtop. Made by OTWIN - the luthier Otmar Windish.
I don't know enough about the Otwin brand, but the famous guitar-guide book, the Blue Book sais that "OTWIN Instruments previously built in East Germany in the late 1950s to early 1960s.
Instruments with the Otwin brand name were built by the Musima company in Germany during the late 1950s on. Earlier models were available in original designs
of both solid body and semi-hollowbody configurations through the early 1960s." that's all.
This one is the top-of-the line model by Otwin called DE-LUXE. The silid spruce top and flamy solid maple back having the legendary German Carve.
You can find the shape of F holes are similer with of the ROGER (Wenzel Rossmaissl). So this would be the copy model of the Roger.
All are original except the Original Tailpiece that already broken was replaced the Japanese newer wood (ebony) one.
I bought this from the English guitarlist whose father bought this originally in 1954. (The son gave me the photo of his fathers band with this guitar, that prove it!)
Nut width 44mm, Scale Length 640mm, Body width 405mm, depth 90mm. Acoustically warm sound but not loud.