Raytheon JAN6418 sub-mini valve portable headphone amp

Just when you thought you had seen it all something "different"comes along. This 9V valve front-end headphone amp/driver is based on a Oatley Electronics (Australian) kit. I built the kit stock standard and loved the sound. Then upgraded most parts to make a "Signature" strength preamp version. A L4949 5V regulator chip and PT2308 headphone driver come with the kit which also has two Raytheon JAN6418 sub-mini valves. As a preamp (replace the PT2308 with an OPA2134) or headphone amp the kit is excellent. I run both on two 9V lithium batteries in parallel.The amp only draws 12mA! Soundstage is excellent and bass rich and extended. The bandwidth is <10hz to 50Khz (-3db points).

See the JAN6418 Valve (Tube) Preamplifier / Headphone Amp Kit project page for full details.