Looking for the font used for the lettering "SOUND" Discothek

Hi you all :),
while working last night I had an idea, for the realization of which I would need the font that was used in the lettering of the Berlin disco named "SOUND" during the 1970s. Unfortunately, I had to find out for myself that none of the font finders can come up with a result, which is no wonder looking at the image quality. Unfortunately I can't find any better images of the lettering on the Internet. Therefore I hope for your help 🙂 
Thank you very much in advance 🙂