Yamaha YM3526

The YM3526, a.k.a. OPL (FM Operator Type-L), is a sound chip developed by Yamaha as a low-cost nine channel, two operator FM synthesis chip. It was notably used in a Commodore 64 expansion, the Sound Expander, as well as several Arcade games, such as Terra Cresta and Bubble Bobble.

A very closely related chip is the Y8950, or MSX-AUDIO, which was used as an MSX expansion. It is essentially a YM3526 with ADPCM recording and playback capability.

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