Technics SU-GX70, smart sound amplifier with network player

The SU-GX70 uses a fully digital amplifier with Technics' renowned digital audio technology. The digital transmission system processes signals digitally throughout the entire process, from input to output. Compared to analog transmission, this system is less susceptible to signal degradation due to external noise, resulting in more accurate signal transmission. The precise signal processing not only delivers high-resolution digital sound, but also reproduces the smooth texture inherent in analog recordings.
Additionally, the JENO Engine is used in ARC (Audio Return Channel), a first for a Technics product. This helps reduce sound quality degradation caused by fluctuations in digital audio signal transmission (S/PDIF), and ensures an unparalleled level of TV sound clarity.

The impedance of a speaker changes with each frequency, and an amplifier is required to drive speakers without being affected by the speaker characteristics. However, conventional digital amplifiers are connected to the speakers through a low-pass filter at the output stage, so they are even more affected by the speaker impedance characteristics. Furthermore, although the amplitude characteristics of conventional amplifiers have been improved by negative feedback, the phase characteristics have not been improved.

So we developed an adaptive speaker impedance optimization algorithm that adjusts the ideal impulse response by processing the digital signal by measuring the amplitude-phase characteristics of the amplifier frequency when the speakers are connected. This method allows for equalization of the amplitude and phase-frequency characteristics, which was previously not possible with amplifiers, and also creates sound with rich spatial expression.

Power supply design is particularly important for audio systems that contain amplifiers, digital circuits and other similar components. To eliminate any negative effects on the amplifier, the SU-GX70 uses a dedicated power supply for the amplifier circuits, which is not connected to any other circuits. The same electrolytic capacitors installed in the most modern models are used in both the dedicated power supply for the amplifier and the power amplifier components.

The SU-GX70 uses a high-speed switching power supply of approximately 130 kHz. By increasing the switching frequency, noise interference in the music playback bandwidth is reduced. This allows the use of a highly responsive power supply for music signals and ensures powerful speaker speed.

In order for the SU-GX70 to receive audio signals via HDMI ARC (Audio Return Channel), video signals must first be sent from the SU-GX70 due to specifications. However, the output of these signals may cause unwanted noise.
Video signals from the SU-GX70 are sent at a lower rate, and the digital color value of each pixel is set to zero. This ensures that the interaction loads between HDMI transmitters and receivers are low, thus preventing unwanted noise from the video signals. This further reduces any impact on sound quality. In addition, by transmitting signals from the TV to the JENO Engine via the shortest possible path, the effects of jitter are even less noticeable. This mechanism is a unique feature of Panasonic/Technics, HDMI licensees.

In pure boost mode, power is cut off to the network and HDMI circuits to reduce noise from the device or antenna, ensuring that your music sounds even clearer.

The circuit used in the SU-R1000 has been redesigned and adapted for use in the SU-GX70 as a discrete amplifier circuit, while maintaining the same symmetrical layout.
In addition, parts of the same level as those used in the SU-R1000's high-quality audio system, such as low-noise FETs, thin-film resistors, film capacitors, and electrolytic capacitors, are used, ensuring that the unit is matched down to the smallest detail.