This is the PCB of an absolutely audiophile grade headphone amplifier, using two of the best opamps in the world, AD797 and BUF34 for the voltage gain and current driving stage respectively. The circuitry is reference to RSA XP-7 headphone amp which has received rave comments all around the world. The circuit can be fed by either external DC or two 9V batteries( for best noise performance). We provide schematic and part list to buyers by EMAIL. PCB dimension: 58mm x 137mm. PCB thickness 2mm. Super thick copper ( 2oz) is used, which is three times the normal thickness.Gold-plated surface. We do air shipping worldwide at US$4.50. We welcome combine shipping. Track Page Views With Auctiva's FREE Counter Powered by SoldEazy