Parrot + II

 Parrot de Tony Ramos, Alpha Systems

https://www.atarimagazines.com/v2n4/talkischeap.html

https://www.atarimagazines.com/v8n8/anticsamplingproc.html

https://forums.atariage.com/topic/329129-parrot-hardware-any-information/

https://www.atarimania.com/utility-atari-400-800-xl-xe-parrot-digital-sound-system_29705.html