[Simon] wrote in to tell us about a headphone tube amp that he just ... s] design adds an on board regulated power supply and a volume control for the input. Effort was made to keep the PCB ...

Deciding to go for a full digital design for the circuitry, the peripheral is based off of a MEMS microphone and an ... noise and then ST’s own Smart Volume Control filter, which works more ...

which might require you to boost the microphone volume. However, this method works considerably better if you connect a pair of headphones to your speaker’s headphone jack to prevent the sounds ...