I get that my solution is a little more expensive. But, actually the whole thing costs ~$25, not $40, if you buy the three components thriftly (used Pi ~$15, us

I get that my solution is a little more expensive. But, actually the whole thing costs ~$25, not $40, if you buy the three components thriftly (used Pi ~$15, usb audio adapter $5, mcp4725 $5). In contrast, that link you mentioned has over 15 parts instead of 3 parts, and it needs to be on a PCB/breadboard. The total cost is cheaper (probably $10 if your thrifty) but requires way more effort IMO than using a Pi. Crucially, I've never seen any MIDI to CV that provides a method for automatic tuning which is very time consuming. Using a Pi provides that easily and automatically with sox.