Technics SU-GX70, smart sound amplifier with network player

The SU-GX70 uses a fully digital amplifier with Technics' renowned digital audio technology. A digital transmission system processes signals digitally at all stages, 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. Accurate signal processing not only delivers high-resolution digital sound, but also conveys the smooth texture characteristic of analog recordings.
In addition, the JENO Engine is used in ARC (Audio Return Channel), the first time a Technics product has been installed. This helps reduce audio quality degradation caused by fluctuations in digital audio signal transmission (S/PDIF) and provides an unmatched level of clarity in television audio.

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

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

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

The SU-GX70 uses an approximately 130 kHz fast switching power supply. Increasing the switching frequency reduces noise interference in the music playback bandwidth. 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 introduce unwanted noise.
Video signals from the SU-GX70 are sent at a slower rate, and the digital color value of each pixel is set to zero. This ensures low interaction loads between HDMI transmitters and receivers, thus preventing unwanted noise from 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 effect of fluctuations is even less noticeable. This mechanism is unique to Panasonic/Technics, HDMI licensees.

In pure gain mode, turning off the power to the network and HDMI circuits reduces noise from the device or antenna. This ensures that the reproduced 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, maintaining the same symmetrical layout.
In addition, the same level of high-quality audio system components used in the SU-R1000, such as low-noise FETs, thin film resistors, film capacitors and electrolytic capacitors, are applied. In this way, the device is compatible down to the smallest details.