Technics issues its Reference Class products in pursuit of delivering the ultimate in sound quality to its customers and the SU-R1000 integrated amplifier continues to evolve the company’s digital amps.
While fully recognising that many high-end audio amplifiers are analogue, with the mature technology boasting a long and well established history, Technics is also highly aware of the rapidly evolving and improving field of digital amplification too, with high-accuracy signal processing now available that is not possible with analogue systems. Since so many of today’s mainstream music sources are digital, such as CD and streaming platforms, these signals should ideally be processed in the original digital format and, with AD converters also advancing, high-precision digital signal processing of analogue music sources is improving all the time.
Since initialising its digital amp development programme in 2014, Technics has created and refined a number of technologies which now find themselves at the centre of the new SU-R1000 and its latest advanced Digital Amp Technology.
Combining established proprietary technologies such as LAPC (Load Adaptive Phase Calibration) and JENO (Jitter Elimination and Noise-Shaping Optimisation) with Technics’s newly developed ADCT (Active Distortion Cancelling Technology) helps to eliminate distortion generated in the power stage.
A new switching power supply system, Advanced Speed Silent Power Supply, has successfully improved the S/N ratio within the amplifier, while four independent power supply units provide for different circuit blocks to realise improved separation and dynamic sound reproduction.
And since Technics make some of the most popular turntables on the market and vinyl fans form an important market segment for the company, an Intelligent Phono EQ has been implemented which achieves a more accurate equaliser curve and delivers better sound quality via digital technology.
The new amp comes with an abundance of input and output terminals, including Phono XLR Input and two USB-B Input terminals, to handle a broad range of analogue and digital audio sources and peripheral equipment.
The Technics SU-R1000 Reference Class integrated amplifier is available from November 2020 and is expected to be priced at around €8000 with a choice of silver and black finishes.
There’s more technical detail provided in the Technics Press release quoted below:
High Sound Quality Technologies Incorporated in SU-R1000
JENO (Jitter Elimination and Noise-Shaping Optimisation)
Jitter is a major cause of distortion in digital systems, and is caused by mis-timing in the master clocks used in digital-to-analogue conversion. To eliminate the degradation of sound caused by jitter, Technics has developed an original jitter reduction circuit, comprising a clock generator in the noise-shaping system to reduce jitter in the low-frequency range and a highprecision sample rate converter for suppressing jitter in the high-frequency range. Thus it reduces jitter in an ideal way over the entire frequency range. This works with original highprecision PWM (Pulse Width Modulation) conversion circuit, optimising the noise-shaping speed, the degree and re-quantisation number, and the PWM gradation, in order to convert high-resolution signals to PWM without causing any damage to the dynamic range. These technologies enable Technics digital amplifier designs to reproduce the natural and delicate nuances of music.
LAPC (Load Adaptive Phase Calibration)
Speaker impedance changes with each frequency and a power amplifier is required to drive speakers without being affected by the speaker’s characteristics. However, conventional digital amplifiers are connected to speakers through a low-pass filter at the output stage, so they are even more strongly affected by the speaker impedance characteristics. Also, although the amplitude characteristics of conventional amplifiers due to negative feedback were improved, the phase characteristics could not be enhanced. We thus developed a speaker impedance adaptive optimisation algorithm that performs correction to the ideal impulse response through digital signal processing by measuring the frequency amplitudephase characteristics of the amplifier with the speakers connected. This new technique enables flattening the frequency characteristics of amplitude and phase, which had previously not been achieved by amplifiers, as well as delivering a sound with rich spatial expression.
ADCT (Active Distortion Cancelling Technology)
The Active Distortion Cancelling Technology newly developed by Technics accurately extracts and removes distortion in the power output stage which is generated by the speaker’s counter electromotive force and voltage drops. In the Hi-Fi audio market where an unlimited number of audio systems can be configured by combining various products, highend audio amplifiers need to drive a diversity of speakers to the fullest. The Active Distortion Cancelling Technology accurately extracts distortion by determining the difference between the speaker terminal output and JENO output and then applies correction to the output digital signal, thus correcting the conventional digital amp system. This provides powerful speaker driving force and acoustic energy while offering the superior features of the digital amp, such as low noise, sharp sound image and expansive sound ambience, regardless of the types of connected speakers.
Advanced Speed Silent Power Supply
The SU-R1000 uses a switching power supply system to ensure stable supply of voltage and current required by the digital amp. In a conventional switching power supply system, the ON time of the switching operation was controlled in order to stabilise the voltage, and this caused the switching frequency to fluctuate according to the load, resulting in a modulation noise to affect the sound quality. The Advanced Speed Silent Power Supply has eliminated this noise by fixing the switching frequency in the 400-kHz band. Furthermore, a Super Low Noise Regulator is provided in the later stage. This prevents the decrease of regulation resulting from the fixed switching frequency and impedes the mixing of noise component into high frequencies. The result is high-response power supply that brings out the best performance from the digital amplifier.
Four Independent Power Supply
Units In the SU-R1000, every element comprising the power supply has been revamped for higher sound quality. What’s more, four independent power supply units are provided for different circuit blocks for further enhancement of sound quality. Since the SU-R1000 is an integrated amplifier, the internal circuits consist of a pre-amp stage and power amp stage in a mix of analogue and digital circuits. The Phono-EQ section which processes minute analogue signals is particularly susceptible to the effect of noise transmitted through the power supply line. The SU-R1000 uses separate power supply units for the analogue circuits and digital circuits in the pre-amp stage. It also uses separate power supply units for the right and left channels in the power amp stage that requires large electrical power. With the four independent power supply units, the SU-R1000 prevents power-line-induced interference among the circuit blocks and realises a high S/N ratio and superb separation.
Battery Driven Clock Generator
For a digital amplifier, improving the precision of the clock, which provides the important operation timing information, is the key to high sound quality. However, power supply noise from the clock circuit is a major impeding factor. The SU-R1000 is equipped with a Battery Driven Clock Generator. The use of a battery as a power supply for the clock circuit eliminates the adverse effect of power supply noise on the clock signal, thus enabling superb sound image localisation and clear sound space expression.
GaN-FET Driver (High Speed and Low Impedance Power devices)
In the power output section of the amplifier, Technics has employed a high-speed GaN (gallium nitride) FET driver device with super-low resistance. This enables the construction of a high-power amp using a single push-pull configuration, allowing the length of the large current carrying signal path to be shortened, and resulting in outstanding linearity regardless of the sound level.
Intelligent Phono EQ
The Intelligent Phono EQ mounted in the SU-R1000 utilises the sound quality improvement technology for DSP, which Technics has accumulated through the development of LAPC, in order to realise high sound quality not possible with analogue Phono-EQ. This technology consists of three parts: 1. Accurate EQ Curve, 2. Crosstalk Canceller and 3. Response Optimiser. These functions can be turned ON/OFF to suit the user’s preference.
1. Accurate EQ Curve A
ccurate EQ curve is achieved by a hybrid analogue-digital system. The high-gain lowpass filter (LPF) performs analogue processing, and high frequencies are raised after the A/D conversion. The use of the 40-dB LPF in the analogue region suppresses the bit loss during digital filter processing, and high frequencies are raised with high accuracy in the digital region to achieve a high S/N ratio.
2. Crosstalk Canceller
This function measures the crosstalk characteristic of the installed cartridge by using the crosstalk measuring signal recorded on the Calibration Record bundled with the SUR1000 and then performs reverse-correction using the built-in DSP to achieve significant improvement of the crosstalk characteristic. This results in sharper sound image and more expansive sound ambience.
3. Response Optimiser
This function measures the frequency characteristic of the installed cartridge by using a TSP (Time Stretched Pulse) signal recorded on the bundled Calibration Record, and corrects characteristic disturbance. It corrects the effect of impedance matching. between the cartridge and phono equaliser to bring out the true sound quality of the cartridge. This technology aims to improve sound quality by providing a selector such as a switch in the high-sensitivity phono input line for the removal of the possibility of noise mixing
Source: Press Release
Image Source: Technics