Every so often, I like to check out the headphone amp scene at [headwize]. The headphone lovers there never seem to stop. This little amp is one of the latest creations. The latest is the mini v3 – it reflects a trend I’ve been seeing on homebrew hardware: SMD core chips and through hole components for support hardware. A 9 volt supplies power, and a pair of linear regulators. It’s a nice simple, solid design – and you’ve gotta love the thumb screws. (I’m not sure how a more efficient PWM regulated power source would affect the audio output)