Indeed, the article is very unsophisticated. Here are some relatively inexpensive measurement mics: https://roga-instruments.com/usb-measuring-microphone/ https

Indeed, the article is very unsophisticated. Here are some relatively inexpensive measurement mics: https://roga-instruments.com/usb-measuring-microphone/ https://roga-instruments.com/usb-measuring-microphone/ Going the USB route sidesteps the separate DACs, which either add to the problem or run into the thousands.