Here's a project that's been in the pipeline for about 6 years. It's a simple chip-amp style headphone amp that has at its heart a TDA2822M dual op-amp IC. It's powered by a 9V 500mah "wall-wart" style power adapter. It's enclosed in an old TV RF/RCA input adapter case that I had in my junk-box. The old case was luckily very well built. It's all steel and held together by nice metric phillips screws. I had fun cleaning up and modding the case with my dremel, some black spray paint, and some scrap plexi for a window. It sounds pretty good with a noticeable difference in the depth of the sound range. Unfortunately, there is a light but noticeable hiss. I think I need to play with resistor values, but I'm new to this type of electronics so I'm sure it could be a lot of things. There is a wealth of info all over the web for these types of projects, which I highly recommend, as it's not that hard to get good results. Sites I found that especially helped were found here and here . The schematic I used is from E-Dan.
