Soundcards were huge long 8-bit ISA things that would take up huge amounts of real estate in a desktop computer. Nowadays, for most of us, they are baked on the motherboard and we rarely think of them a second time. [Samsonov Dima] Decided to whip up a cheap sound card of their own, however, built around the STM32.
The soundcard is specifically based on the STM32F401. “Green Peel” is readily available on the Devboard. A digital-to-analog converter is applied to the board based on two PWM timers that provide high-quality output. There is also a simulated software called Sigma Delta ADC that is applied between audio streaming and actual PWM output via USB, some innovative techniques used to improve the sound output. [Samsonov] It was even found while adding a display with twin VU meters that showed audio pumping through left and right channels.
Without hands-on test gear, we can’t easily measure the performance of a sound card. However, according to the YouTube video posted, it seems to be able to recreate the music with good fidelity and lots of subtle details.
If you need a cheap, simple USB sound card that you can hack, this might be for you. If you need something more suitable for a vintage PC, consider it instead. Video after the break.