The author built the hardware equivalent of a toy/gimmick. In software terms, this is a quick script/widget under a hundred lines of code. The chip is over ten

The author built the hardware equivalent of a toy/gimmick. In software terms, this is a quick script/widget under a hundred lines of code. The chip is over ten years old and technology has improved a lot more. Four thousand dollars is not a feasible amount to manufacture any significant quantities of hardware (it's barely enough budget to do a prototype). 40 thousand and a high end FPGA or a more up to date amplifier mounted on a shield would be a lot better for this application.