Built like a tank Kenwood KA-7010 this is pre-main amplifier with improved speaker drive performance under low impedance load. The power supply has a dedicated transformer on the positive side and the negative side respectively. The power transformer has a large capacity of 420 VA and is equipped with an electrolytic capacitor of 7500 μ Fx4 with a total capacity of 30000 μ F. A high power transistor of Pc = 200W is used for the output stage of the power amplifier to improve the drive performance under low impedance load. We have developed and adopted a pure signal ground line to prevent distortion caused by mixing of the music signal and power ground lines. In this system, the power supply ripple and various noise components are led to the speaker terminals by a dedicated ground line, and all the ground lines are connected so that all the ground lines join together for the first time. As a result, only a pure signal flows through the main ground line that amplifies the signal, enabling pure amplification. Consideration is given to the internal layout in order to minimize the signal path and eliminate mutual interference between components. The volume is placed in the center, and the internal layout follows the theory of INPUT → SELECTOR → VOLUME → POWER AMP → SPEAKER. The EQ amplifier uses ICL high GmFET differential inputs and integrated circuits. A source direct circuit is mounted. Specs : Power output: 100 watts per channel into 8Ω (stereo) Frequency response: 5Hz to 100kHz Total harmonic distortion: 0.006% Damping factor: 160 Input sensitivity: 0.2mV (MC), 2.5mV (MM), 150mV (line) Signal to noise ratio: 70dB (MC), 78dB (MM), 80dB (line) Channel separation: 52dB (MM), 55dB (line) Output: 150mV (line) Speaker load impedance: 4Ω to 16Ω Dimensions: 440 x 148 x 398mm Tested and everything works ! Please note one of the AUX input has a missing red circle. Please check pictures provided.