a sound chip introduced in 1991 by Yamaha for their first General MIDI-compliant synthesizer, the Yamaha TG100. It also appeared on a number of higher-end consumer keyboards and specialized professional devices. The YMW258-F implements the GEW8 sound synthesis technology, which is PCM sample-based synthesis under Yamaha's "Advanced Wave Modulation" (AWM) umbrella.
Sega used the chip in several arcade games on the Sega System Multi 32, Sega Model 1, and Sega Model 2 arcade boards. The chip as found on these boards is called MultiPCM, and has the Sega internal part number 315-5560. Contrary to popular belief, it is not a custom Sega part and is not based on the earlier SegaPCM chip, but it was named the MultiPCM as a successor to that chip.
it has a whopping 28 channels of stereo 16-bit PCM and:
- hardware LFO
- 8bit and 12bit wave format support
- up to 4MB of wave memory
- full blown ADSR envelopes
## effects
-`20xx`: **set PCM LFO rate.**
-`21xx`: **set PCM LFO PM depth..**
-`22xx`: **set PCM LFO AM depth.**
## info
this chip uses the [MultiPCM](../4-instrument/multipcm.md) instrument editor.
