A Moogle  🏳️‍🌈 💻 🎮 🎶 🇸🇪

Seeing all these 70's/late 80's arcades get actual sound emulation is great, I knew they were missing because it was super hard to get right or something. Sorry to ask but what exactly is netlist audio?

MAME contains within it a library that allows for realtime simulation of a network of analog or digital components. Similar products like SPICE and PSPICE have existed for decades, but have traditionally run much slower realtime, rather than at or faster than realtime.

*much slower THAN realtime. I forgot a word. It's called a "netlist" because it's a list of nodes that are arranged to form a network of discrete components. Suppose you have a 47KOhm resistor marked R32 on the schematic, you'd declare it as RES(R32, RES_K(47)).

Then if you have a 0.1-microfarad capacitor C14, it would be CAP(C14, CAP_U(0.1)). Finally, supposing a leg of the resistor is connected to a leg of the capacitor, you would do: NET_CONNECT(C14.1, R32.1)

With some exceptions, if you have a complete list of components from the audio section of an arcade board and take the time to exactly transcribe how they are interconnected, then with a bit of glue logic in the MAME driver, it Just Works™ and gives you audio.

The primary exceptions generally involve certain types of noise-generator circuits. By running a standard bipolar-junction transistor against the rails to the point it hits reverse breakdown, you can use it as a noise source. This does not work, for various reasons.