OKI MSM6295

an upgrade from 6258 - it provides 4 ADPCM channels, at max 32 KHz (still no variable pitch though). between late 80s and late 90s, it was one of the most common, if not THE most common soundchip used in arcade machines (Capcom, Toaplan, Kaneko, Atari, Tecmo, the list can go on and on...)