The MA-2 was the second SMAF-compatible audio LSI to be released by Yamaha. As well as incorporating all the features of the MA-1, it also includes a raft of new features which greatly extend the possibilities for the creation of content for mobile phones and other hand-held devices.

In addition to its built-in FM sound generator, the MA-2 also incorporates an ADPCM sound generator which enables the reproduction of digitally recorded natural sounds, such as human voices. As a result, it is possible to author content which combines a person's voice and his image. In addition, the MA-2 can precisely synchronize compressed audio from its ADPCM sound generator with performances that use the FM sound generator. This feature can be used to provide a backing chorus for a melody.

The MA-2 provides a standard library of 256 instruments (including the 128 instruments specified by the General MIDI standard) and an unlimited range of voices. In addition, the MA-2 boasts 16-note polyphony. This feature can be used either to create 16-note harmonies or to play notes with 16 different timbres.

The MA-2 incorporates a built-in hardware sequencer which can reproduce music data with little CPU overhead. Hence, the LSI can reliably play back complex melodies in synchronization, and still leave the CPU relatively free to perform other processing. The MA-2 also features a sound vibration function which can control a mobile phone's vibration timing. Using this function, vibrations can be synchronized with the beat of music accompanying a mobile phone-based game.

The MA-2 includes a built-in amplifier for driving dynamic speakers which delivers an output power level of 550 mW. The chip also includes a built-in equalizer circuit which compensates for the frequency characteristics of a speaker or handset. Despite these advanced features, the MA-2 is contained in a miniature package, allowing its easy incorporation into the design of a mobile device.

Major Features		FM sound generator Polyphony: 16-note polyphony (16 independent sounds can be generated simultaneously.) ADPCM playback function: single-channel 4-bit ADPCM decoder Sampling rates: 4 kHz, 8 kHz Stereo Hardware sequencer Speaker amplifier (maximum output: 550 mW) Equalizer circuit to optimize frequency characteristics of sound for speakers 16-bit stereo D/A converter Analog stereo headphone output Current drawn in Standby mode: less than 1 µA (typically)
Power Supply		Analog system power supply for speaker amplifier: 2.7 V to 4.5 V Power supply for all other systems: 2.7 V to 3.3 V
Fabrication Process		CMOS
Package		32-pin plastic QFN

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Sound Chips and Handsets