Sound: Yamaha YM3812 (OPL2)

A proper 8bit computer also needs a proper sound chip. And by sound chip we mean a proper sound chip, which creates sounds, not a DAC-based device that just plays back samples.
And by thinking sound chip and 8bit, the first thing comes to mind is of course the MOS 6581 SID chip, prominently used in the C64 and hands down the best sound chip from the 8bit era. But the SID has a few drawbacks that would make it difficult to use for the Steckschwein:

  1. It’s maximum clock rating is 2MHz. We’re already running at 8MHz, so that’s going to br a problem.
  2. While not hard to come by, SID chips aren’t cheap. Prices of about 40 Euros or more per unit are common. And those chips are not NOS, they are most likely pulled from a C64. We do not want to build the Steckschwein out of scavenged parts.

We decided to use the Yamaha YM3812 chip, which might be better known as OPL2. That’s right, the very chip that was used on early PC sound cards such as AdLib or the first Sound Blaster cards. OPL2 chips are easy to come by, and they are rather cheap.

 

opl2_mono

YM3812 und sein DAC YM3814 im Steckschwein