A Totally Lost Audio Format: Sanyo’s Micro-Pack
Even though I’m something of a student of lost recorded music formats, I’d never, ever heard of the Sanyo Micro-Pack until David forwarded me this link.
After Earl Muntz introduced the 8-track and while Phillips was working on the compact cassette, Sanyo was working on a format that fell exactly between the two. Like the 8-track, Sanyo’s Micro-Pack jammed an endless loop of tape inside a plastic cartridge. Like the cassette, it was smaller. Sanyo’s goal in 1964 was exactly the same: bring the fidelity and versatility of reel-to-reel tape into a miniaturized realm so the technology could be made cheaper and above all portable.
The Micro-Pack’s tape ran diagonally, driven but a finicky rubber wheel. In the lab, this worked great. But in the wild, that wheel didn’t drive the tape smoothly, resulting in uneven speeds and music that had an annoying warble.
No pre-recorded music was ever released in this format and if any were ever sold to consumer, the Micro-Pack sunk out of site.


I had one of these! My grandmother was a gadget fan in the ’60s and bought all sorts of terrible new rubbish. I discovered it in a cupboard in the ’70s. I could never get it to work properly.
I don’t think there’s even a Wikipedia article on this format. I should probably start one.
There is, as of 17.10.05, an article on the German wikipedia: https://de.wikipedia.org/wiki/Sanyo_Micro_Pack_35. Have you created an English article yet?
Also, do you still have your’s, and are you willing to sell it?