There are 5 artists with the name "A4":
1. A Dutch Punkband. The members were Martin Woudstra, Harry (later Paul), Geurt (Ex-Ex) drums & Charlotte Smits played bass (later some one else, don't know the name). They stopped at the end of 1983.
2. A Korean boyband. Lead vocal was Wheesung.
3. Former name of UK rapper Josef Motley of swampglow and Tortoiseshell Male, active between 2003-05.
4. A jazz group from Turku, Finland. Their album "Changes" was released in 2009.
5. A rap group from Azerbaijan. Read more on Last.fm