CREATE TABLE table_27178 ("Year" TEXT, "Amiga demo" TEXT, "PC demo" TEXT, "C64 demo" TEXT, "Amiga intro" TEXT, "PC intro" TEXT)

What won best amiga demo when alto knallo (free electric band) won best pc demo?
SELECT "Amiga demo" FROM table_27178 WHERE "PC demo" = 'Alto Knallo (Free Electric Band)'
SELECT "Amiga demo" FROM "table_27178" WHERE "PC demo" = 'Alto Knallo (Free Electric Band)'