Hi everyone,

As many will know, Yamaha manufactured five sound generator LSIs that were (or are) present in cell phones.
MA-1, MA-2, MA-3, MA-5 and MA-7.

Each of these chips has a limited polyphony, of 4 notes up to 128 notes and with different features. FM, PCM, etc.

In this post I will list each of the sound generators, along their respective features.

MA-1 (YMU757B-Q)

The YMU757B-Q, was the first sound generator LSI compatible with SMAF that was released by Yamaha.

The built-in FM sound generator of the YMU757B-Q (in this case, the MA-1) can generate 128 different tones (the 128 instruments specified by the standard General MIDI). It produces a high sound quality, and there are no limitations on the tones that can be created, the MA-1 can be used to generate a variety of different sounds.
The MA-1 has 4 polyphony notes. This function can be used to create 4-note harmonies or to play notes with 4 different timbres.

MA-2 (YMU759B-Q)/MA-2L (YMU759C-QZ)

The YMU759B-Q was the second sound generator LSI compatible with SMAF that was released by Yamaha. In addition to incorporating all the features of the MA-1, it also includes a number of new features that expand the possibilities of creating content for mobile phones and other portable devices.

In addition to its built-in FM sound generator, the MA-2 also incorporates an ADPCM sound generator that allows the playback of natural sounds recorded digitally, such as human voices. As a result, it is possible to create content that combines a person's voice and image. In addition, the MA-2 can accurately synchronize the compressed audio of his ADPCM sound generator with functions that use the FM sound generator. This function can be used to provide an accompaniment chorus for a melody.

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

MA-3 (YMU762-Q)/MA-3L (YMU762-CZ)

The YMU762-Q is the third sound generator LSI compatible with SMAF that was released by Yamaha. In addition to incorporating all the features of the MA-2, it has several enhanced features that further expand the possibilities of creating mobile content.
In addition to its built-in FM sound generator, the MA-3 also incorporates an ADPCM sound generator that allows the reproduction of natural sounds recorded digitally, such as human voices. As a result, it is possible to create content that combines a person's voice and image. In addition, the MA-3 can accurately synchronize compressed audio from his ADPCM sound generator with performances that use the FM sound generator. This function can be used to provide an accompaniment chorus for a melody.

And a new feature of the MA-3 is that it incorporates a waveform table synthesizer that generates 8 instruments/voices simultaneously.
The waveform data can be downloaded from ROM or RAM. Since the waveforms can be adjusted arbitrarily for FM operation, the range of tones that can be generated is much higher than in conventional devices.

The MA-3 adopts a system of hybrid stereophonic synthesizers that allows the simultaneous generation of up to 40 tones: 32 FM + eight waveform tones. This function can be used to create 40-note harmonies or to play notes with 40 different timbres. In addition, the MA-3 offers a standard library of 256 instruments (including the 128 instruments specified by the standard General MIDI) and an unlimited range of voices.

MA-5 (YMU765)/MA-5S (YMU769)

MA-5 is a versatile hybrid sound chip that combines five types of sound generator systems. FM, WaveTable, PCM, AL (Analog Lite) and HV (Humanoid Voice). It is capable of playing up to 64 notes of polyphony, which enriches the sound and improves the expression of the effect and the stereo feeling. The MA - 5 is an LSI that is optimal as an output device for sound handled by mobile phone terminals, such as advanced game sounds and high - quality incoming melodies (ring tones).

The AL (Analog Lite) synthesizer is newly compatible with MA-5. The analog synthesizer is widely known in DTM (DeskTop Music). MA-5 equips the fundamental function of that analog synthesizer. Using a low pass filter time variant, it allows voice changes that can not be made by the sound chip of the previous generation. These effects are common in genres of electronic music and popular music such as Pops, Hip-Hop and Techno.

On the other hand, the Wavetable synthesizer can download and use any ADPCM / PCM in addition to the tone generation built into ROM.

Another remarkable feature is the sound generator that tries to simulate the human voice.

HV

HV (Humanoid Voice) is a speech synthesis sound generator that simulates human voice. You can handle sounds simulating human voice as sound effects in the game or as instruments sounds in SMAF. The HV sound generator method can be used to express sounds by specifying text data and accent marks, so it is suitable for mobile phones with data size limitations. Human voice is vocalized by the vibration of the vocal cords and uttered by adding resonance depending on how the mouth is open and the shape of the throat, but in the HV sound generator, the frequency spectrum of the voice is re-synthesized and enables playback of voice tone.

Introduction to MA-7

With the development of multimedia in mobile phones, in the future not only ringtones will be streamed, but also applications such as music distribution, video distribution, radio reception, analogue and digital television transmissions and "sound" to be handled in mobile phones. It iss in the direction of diversification.
Backed by these trends, Yamaha has developed the "MA-7 (Yamaha AudioEngineTM)" series as a high-quality, high-performance audio processor for freely processing and playing back these sounds.

YMU786 (MA-7)

YMU786 is the audio LSI which is the base of AudioEngineTM series. Audio processor and analog block such as mixer, headphone amplifier, speaker amplifier, etc. are integrated on one chip.

Features of the MA-7

• An advanced hybrid synthesizer
  Based on the established FM sound generator and proven as the best method for mobile phones, the hybrid synthesizer combines various types of sound generators such as Wavetable, StreamPCM and Analog Lite sound generators.
  Not only ringtones, you can play rich sounds with game sound effects and background music. The maximum polyphony number is 128 notes. It supports SMF and other standard formats as well as Yamaha's proposed distribution format "SMAF".

• Simultaneous playback of multiple sequences
  Up to four MIDI-based sequences, plus a total of eight sequences of four digital audio systems, can all be played simultaneously. The expressive power of game sound has dramatically increased compared to the conventional product. By switching the playback mode, you can also play SMAF and audio simultaneously. It also supports a mode that generates MIDI commands in real time, which is ideal for music games, and music games can be easily realized on mobile phones.

• Multifunctional effector
  Provides versatile effect processing using two independent effects modules. The effects included with the Reverb, Delay, Echo, Chorus, Phaser, and other middle-class electronic instruments are standard.
  For example, "Reverb" allows you to change the overall sound effect (atmosphere) at the moment you enter the tunnel while playing a racing game. In addition, you can use the pitch change to realize a voice change function and express the Doppler effect. The multifunctional effector can customize various parameters freely, and can also make an original effector. The use of multifunctional effectors has dramatically improved the quality of SMAF sound applied to ringtones and game sound effects.

• 3d positioning processor
  You can localice a virtual sound source at any point in the hemisphere that is placed around the head. For example, it is possible to synthesize a rich immersive game sound, such as moving the airplane and the helicopter to the left and right and back and forth, and running the four racing cars freely while flowing the background music by placing a virtual speaker on the left and right. If you embed coordinate points and travel time information as 3d commands in "SMAF", you can add 3d localization effects to the ring tone content.

MA-7's virtual MIDI driver

The MA-7's Authoring Tool includes a MIDI driver which connects to the MIDI ports opened by the "ATS-MA7" and "MCP-MA7" tools. The devices are called "YAMAHA Virtual MIDI Device 0" and "YAMAHA Virtual MIDI Device 1". In 64-bit OSes you need to install loopMIDI and create two MIDI ports named as "YAMAHA Virtual MIDI Device 0" and "YAMAHA Virtual MIDI Device 1" when you open "ATS-MA7" or "MCP-MA7" for use with an external DAW or a MIDI sequencer that allows you to select the MIDI device.

Extra

There are some things that I have not yet understood, but there are probabilities that they are true. The LSIs have several versions or revisions, as you may realize, I mentioned MA-2L, MA-3L, MA-5S, even MA-7 has others versions such as MA-7D (YMU790), MA-7I (YMU791). I have not looked for more information about those, because anyway I will not find anything, unless they are datasheets that I will not understand.

External links

SMAF Global (archived on the Wayback Machine).
My post about SMAF format, sound generator LSI features and the base of this post. (In Spanish).