The YM3438,a.k.a. OPN2C, is a modified CMOS version of the YM2612, commonly used in Sega's arcade system boards. This version has an improved built-in DAC that reduced the peculiar crossover distortions caused by the amplitude voltage errors present in the YM2612. It is not a direct, drop-in replacement for the YM2612 however, as the sound outputs have higher impedance.
- Six concurrent FM synthesis channels (voices)
- Four operators per channel[4]
- Two interval timers
- A sine-wave low frequency oscillator
- Integrated stereo output digital-to-analog converter (most other contemporary Yamaha FM chips require a separate external D/A converter chip)
- Per-channel programmable stereo sound (left, right, or both left and right resulting in centre)
- For channel three, operator frequencies can be set independently, making dissonant harmonics possible. (Normally, they would have a simple relation like e.g. 2× or 3× relative to a common base frequency)