This Wikipedia article makes passing reference to the Grundig Deutsche Cassette, a format I’d never heard of.
Anyone have any details about it? A Google search was fruitless.
I never heard of it too. According to this German-language article (originally published in 1983) it was a derivative of the 8-track format.
According to this Grundig , and Sony, had an early 4 track standard, but the Phillips standard won . Sony and Grundig then switched to the Phillips standard , making the standard stereo cassettes.
http://www.sony.net/SonyInfo/CorporateInfo/History/SonyHistory/2-05.html
that doesn’t disprove there was a specific to Grundig 8 track standard, but you can find Grundig 8 track devices from the same time, that don’t seem to be described as “not the standard 8 track”…
It’s a reference to the Grundig DC-International Cassette (co-developed with Telefunken and Blaupunkt). Here is a video of one of the DC International players in use. And here is a small info page on the format.