The 4S Universal preamp is a Super Simple Single Stage (4S) line stage preamp that works well with the entire range of 12A_7 tubes - 12AU7,...

Bruce has put together a pair of Cheap Open Baffle Speakers - the COBIES .  Relative to most DIY speakers this open baffle project will be q...

Fostex FE103En DIY Bass Reflex Bookshelf Speakers These small computer desktop speakers were built using the in-expensive Fostex FE103En f...

We are always on the lookout for good headphone amplifiers and here is a great simple tube design that will work with a wide range of headph...