That "head at an angle" was really "head at no angle," allowing them to use less wood for a neck. It's similar to the Fender slab neck with string-keeper. Without a back-angle, the strings don't sit in the slots of the nut very well, and so you need something to put some back-pressure on 'em.

"From the heart of Bavaria," Framus guitars and banjos were idiosyncratic to say the least. I once considered buying a Framus 'Texan' model (Gibson J-45 copy), but luckily someone else bought it and it was gone from the shop once I came back.

Bob Clayton