1 pcs portable headphone amplifier less hd8 single end hi dynamic for hi end user opamp earphonel audio headphone amplifier

less hd8 full discrete single end amplifier suitable for portable hi-end user,design base on the sounds natural,and hi dynamic . hd8 is base on marantz classic hdam circuit to modify ,increase all the transter idle current and output power,and push the circuit working on class a operation,make the output voltage more stable, line amp first step using hi-end twins jfet 2sk389bl,keep the preformance