Headphone amplifier circuit using dual operational amplifiers such as OPA2604

The picture above shows a very popular headphone amp made of operational amplifiers on the Internet. Of course, it can be replaced by other dual op amps to obtain different timbres. In the picture above, using two amplifiers can increase the current output capability and thus promote High-impedance headphones, most high-end headphones are high-impedance. It is more popular to use OP234 or OP2134 (dual operational amplifier) ​​as a headphone amplifier on foreign websites, because the operational amplifier has good performance when working at low voltage, which can be conveniently powered by batteries. Made into a portable headphone amplifier.