[Simon] wrote in to tell us about a headphone tube amp that he just built. It is based on schematics at diyaudioprojects.com that were actually featured on Hackaday in the past. [Simon’s ...

It would be interesting to subject it as a headphone amplifier to a series of audio tests to evaluate the effect of a mains transformer over a dedicated audio one.

Transform your Raspberry Pi into a high-fidelity music player with the Pimoroni Pirate Audio Headphone Amp, with a 24-bit DAC ...