VST2413 is a software FM synthesizer based on YM2413 (OPLL) emulator. YM2413 is well known as low-cost FM sound chip, and was used on Sega Master System and FM-PAC sound expansion cartridge for MSX.
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VST2413 can resemble that warm texture of sound and may be well suited for use in "post 8-bit era style" chiptune music.
An implementation of YM2413 emulator (emu2413.c) used in this software is created by Mitsutaka Okazaki. A BIG THANKS goes to him.