The Super IC-12 "high fidelity monolithic integrated circuit amplifier" was launched in June 1971, replacing the troublesome IC-10. It was claimed by Sinclair to be capable of 6 watts RMS. The device was part of the Project 60 range, serving as a hi-fi audio amplifier, although it could be put to use for other purposes as well.

The curious appearance of the amplifier was due to the addition of a outsized heat sink. Predictably, it was nicknamed "the hedgehog". It was a truly tiny device, even with its "fins" - only 22 x 45 x 28 mm including the pins and heat sink. Sinclair's advertisements showed the Super IC-12 standing next to the newly-introduced 50 pence coin - which was only slightly smaller than the device - in order to illustrate its dimensions.