Also SID soundchip from Commodore 64 can be used on ZX. SID is rare and very hard to buy. But exist SID emulator:
http://www.swinkels.tvtom.pl/swinsid/ :v2_walkm:
EXIST SOURCE CODE OF SID PLAYER FOR Z80 CPU (at 6MHz)
http://simonowen.com/sam/sidplay/
http://www.swinkels.tvtom.pl/swinsid...winsidx2_1.jpg

