JENO Engine Amplifier (Distortion Purification and Noise-Shaping Refinement)
To deliver large, high-resolution audio streams to loudspeakers with full fidelity, the SU-G700M2's power section adopts an all-digital amplification scheme driven by the JENO Engine, developed from reference-system principles. To eliminate the sound degradation caused by timing errors common to digital amps, the SU-G700M2 employs a dedicated jitter-suppression circuit that operates across the entire audible band. Sound-significant conversion is handled by a precision PWM conversion circuit designed for PWM (Pulse Width Modulation) processing. By tuning noise-shaping characteristics, quantization steps and levels, and other conversion parameters refined through our engineering experience, high-resolution source material — including wide dynamic range content — is transformed into lossless PWM signals. The result is natural, highly detailed playback that preserves delicate musical expression.
LAPC (Load Based Phase Calibration)
Because a speaker’s impedance changes with frequency, an amplifier must drive that variable load regardless of the speaker design. Conventional digital amplifiers, which route the output through a low-pass filter, are therefore influenced by the speaker’s impedance and, while amplitude response can be corrected with negative feedback, phase response typically remains imperfect. To address this, we created an adaptive algorithm that measures the combined frequency, amplitude and phase response with the speakers connected and then uses DSP-based correction to achieve an ideal impulse response. This approach evens out amplitude and phase irregularities, producing a smoother frequency response and a more convincing, spacious soundstage than previously possible.
Advanced Speed Silent Power Supply
Drawing on the power-system architecture of the SU-R1000 reference, the supply in this model is optimized to deliver stronger speaker drive and a greater sense of energy. To stabilize voltage and current while minimizing modulation artifacts that can color the sound, switching speeds have been raised from the typical 100 kHz band to around 400 kHz. To fully exploit this high-speed topology, the design incorporates the same gallium arsenide (GaN) FETs and silicon-carbide Schottky diodes (SiC SBD) used in the SU-R1000.
The final stage also uses an ultra-low-noise regulator so that a fixed PWM carrier does not degrade regulation or introduce high-frequency noise. The combination yields a quiet, high-performance supply that enables the digital amplifier to perform at its best.
Three-section configuration
An integrated amplifier contains circuits that handle everything from tiny input signals to heavy output currents. The SU-G700M2 separates these into three distinct sections with internal baffles between functional blocks, isolating signal levels to prevent mutual interference and preserve signal purity. In addition to the compartmentalized layout, the chassis uses layered construction — 1.2mm and 2mm steel plates, a 1.6mm steel top panel and a 7mm aluminum front — to suppress vibration and maintain sonic integrity.
Low noise PHONO input
PHONO MC input compatibility has been added. The PHONO input achieves very low noise by using a parallel-differential arrangement of low-noise FET devices at the first amplification stage. Four gain settings let you match the preamplification to the cartridge output, ensuring the best possible reproduction of high-quality analog recordings in your listening environment.
AA headphone amplifier
The SU-G700M2 includes a class AA headphone amplifier that separates voltage and current amplification paths for optimal performance. Voltage gain is provided by a precision op amp, while current drive comes from a high-current output op amp. The refined PWM stream from the JENO Engine is converted with high accuracy, giving excellent drive capability and low distortion across a wide frequency range, independent of headphone impedance.
