I'm traying to make an amplifier following example of Sony TA-N902 Esprit Sere, the last aftre TA-N900 mono and TA-N901 stereo. Sony's Esprit amplifier all haven't Negative Feedback, they had a Voltage Amplifier Stage made by discrete components, which has his proprer feedback and a current stage located out the loop, This architecture decrease the TIM distortion. To minimize THD Sony used his own patent concerning non-switching power devices, the stage also remain a AB class but results similar to pure class A.
3D of the Voltage Amplifiere Stage
Some amplifier are been used as example for schematic or as components donor. Power supply is from a PLPS from an old TA-F80,electronic components for VAS are coming from a TA-F500, the chassis is given by a broken Behringer A500. Other components are new and PCB are made by myself.
Current Amplifier 3D
I used a lot of SMD components, all with 1206 dimension Soon I'll show the complete work