Aiming for the absolute reference sound, any detail in the ADI-2 Pro is special and has its own story. The main PCB is an extraordinary 10 layer design with custom copper thickness, guaranteeing finest undisturbed sound as well as ample but separated power for the phones outputs. Internal power supply stages and precise regulators use a super-low-noise design to not degrade performance through the power rails. Selected SoundPlus operational amplifiers maintain highest SNR, lowest THD and high slew rate under all conditions. The whole analog circuit design is fully symmetrical and balanced throughout - and DC-coupled. The only capacitors in the signal path perform DC protection at the analog input sockets, and have been carefully selected to avoid any sonic impact.