The Yamaha YM2413, also known as the OPLL (FM Operator Type-LL), is a low-cost FM synthesis sound chip produced by Yamaha. It was widely used in various 8-bit and 16-bit computers, consoles, and arcade machines during the late 1980s and early 1990s. It's a simplified version of the more complex YM3812 (OPL2) chip.

Applications

• MSX Computers: A very common sound chip in MSX home computers, significantly enhancing their audio capabilities.
• Arcade Games: Used in some arcade game boards to generate music and sound effects.
• Musical Instruments: Sometimes found in low-end electronic keyboards and synthesizers.
• Sound Cards: Used in some early PC sound cards to provide FM synthesis capabilities.

Features

• FM Synthesis: Uses frequency modulation (FM) to generate a wide range of sounds.
• 9 Channels: Provides nine simultaneous melodic channels.
• 15 Instrument Presets: Includes 15 pre-programmed instrument sounds, such as piano, organ, and guitar.
• Programmable Instruments: Allows users to create custom instrument sounds by adjusting FM parameters.
• Low Power Consumption: Designed for use in battery-powered devices.
• Simple Interface: Relatively easy to interface with microprocessors and other digital circuits.

Benefits

• Enhanced Audio Quality: Significantly improves the audio quality of devices compared to simple tone generators.
• Versatile Sound Generation: Capable of producing a wide range of sounds, from realistic instruments to synthesized effects.
• Low Cost: Made it affordable to include FM synthesis in a variety of consumer products.
• Ease of Use: Relatively easy to program and use compared to more complex sound chips.
• Nostalgia: Evokes a sense of nostalgia for classic video games and computer music.

The YM2413 uses a 2-operator FM synthesis engine. The limited number of operators compared to the OPL2 makes it simpler to program, but also somewhat limits the complexity of sounds it can produce. It features a limited set of waveforms. Despite these limitations, skilled composers and programmers were able to create impressive music and sound effects using the YM2413, and it is still valued for its unique sonic characteristics. The chip is available in DIP (Dual In-line Package).