Soni's Blog


So, nobody really talks about DSD and pulse-density modulation much. So let's talk a bit about them.

For starters, there are no free software tools for dealing with DSD. FFmpeg can only do one-way conversion from DSD to PCM. SoX doesn't support even that. There are no tools.

Secondly, if there were tools, I still don't think we'd see ppl exploring it. So I'm here to encourage ppl to explore it - with the help of old consoles!

Meet the 32X

The 32X is a SEGA Failed Experiment with Catastrophic Failure and was the most failed home console of the 90's. It failed, and it failed hard. Additionally its sound hardware is complete crap - you have a PWM out. that's Pulse Width Modulation. In other words, it's crap.

That PWM output has a variable clock frequency tho. It can work anywhere from 0Hz up to the CPU clock rate - 23MHz. (altho, good luck feeding it samples at that speed! actually you *can't* feed it samples fast enough at that speed!)

You can also use a more manageable sample rate of 2876250Hz (NTSC) or 2850000Hz (PAL) - not far from DSD's 2822400Hz. Note however that this is a multi-bit/PWM output and you can "easily" mix up to 8 streams with this - if you can get the 32X to keep up with it - by just shifting bits around.

So my challenge to you is, can you get better than CD quality out of a 32X?