The new televisions come with Toshiba's bespoke CEVO 4K Quad+Dual Core Processor and use Resolution Restoration to upscale lower-resolution content to near-4K quality.
Other specs Toshiba's crammed into the sets include a 240 Hz refresh rate, UltraClear Dynamic Noise Reduction and built-in Wi-Fi, Wi-Fi and Miracast.
Naturally there are smart capabilities built into the L9300 series too, with Toshiba's Cloud TV offering apps and DLNA access to content on other devices, as well as extra (some would say superfluous) features like a family calendar and photo album.
Toshiba already has one Ultra High Def TV on the market - the first, in fact, in the shape of the Toshiba 55ZL2.
The L9300 series will join it on the shop shelves this summer, with screen sizes ranging from 58-inches up to 84-inches.