*The Spectrum 48K was released in the UK in 1982 and was the successor of the ZX80/ZX81 with upgraded graphics and config (RAM/ROM). The Amstrad CPC464 was released in the UK in 1984 and was a Z80 based computer with AY sound and an a simplified yet upgraded custom IBM PC CGA display for Video.
*Spectrum 48K sold for £99. The CPC464 with Green Screen monitor sold for £299 and with colour monitor for £399. One selling point was that the Amstrad needed only 1 plug, and that you didn't need to use the family television to use it. Also the Spectrum 48k wasn't supplied with any monitor nor storage device.