Technics SU-G700 Stereo Integrated Amplifier (Black)

Description

Stereo Integrated Amplifier SU-G700

Technics’ Definitive Integrated Amplifier Fully Conveys the
Energy of the Music

Reference-class High-quality Audio Technology

Inheriting the reference-class audio technology concept, the
JENO Engine transmits and processes audio signals in full digital and with
minimal jitter from the input stage to the power stage. Speaker load adaptive
phase calibration (LAPC) ensures ideal gain and phase characteristics for any
type of speaker. The newly developed low-distortion switching power supply
realises accurate power supply by suppressing switching frequency fluctuations
caused by load shifting.

JENO Engine (Jitter Elimination and Noise-shaping
Optimization)

In order to faithfully transmit the massive amount of audio
data sent to the speakers without loss, the SU-G700 power amp section uses full
digital amplification employing the JENO Engine, based on the design concept of
reference systems. In order to solve the issue of sound quality degradation due
to jitter, which poses problems for conventional digital amplifiers, the
SU-G700 has an original jitter reduction circuit that eliminates jitter over
the entire audible frequency range. Also, a unique, high-precision PWM (Pulse
Width Modulation) conversion circuit is used for PWM conversion, which is
important for sound quality. By optimising items such as the noise-shaping
speed, degree, and quantization number through our unique expertise, data even
in the wide dynamic range contained in high-resolution sound sources is
converted to PWM signals without loss. These technologies provide reproduction
of natural and finely detailed sound, enabling perception even of delicate
music nuances.

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 amplitude-phase 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.

High-speed Silent Hybrid Power Supply

With a conventional switch mode power supply, the switching
frequency changes in response to the load fluctuation in order to control the
switching ON time for stabilising the output voltage. This fluctuation
component in the switching frequency has a negative impact on sound quality.
The newly developed power supply reduces the noise component harmful to sound
quality by fixing the switching frequency. In addition, the latter stage in the
switching power supply is provided with a linear regulator to stabilise the
output voltage. The linear regulator uses custom, high-definition electrolytic
capacitors.

What’s more, our current resonance-type power supply
decreases the level of switching noise. The parts used for absorbing noise,
such as capacitors, were carefully selected. All possible measures were taken
to achieve low noise and reproduce clear sound.

Digital Noise Isolation Architecture

For the PC input terminals, the amplifier uses power
conditioners with non-magnetic carbon film resistors that provide strong
protection against magnetic distortion, and high-quality ruby mica capacitors
featuring excellent characteristics such as low dielectric loss, high voltage
resistance, and temperature stability. Sound reproduction with greater purity
was pursued by blocking the incursion of outside noise.

Three-section Configuration

In integrated amplifiers there are a variety of circuits,
including circuits that handle the micro-signals of inputs and those that
handle a large current, such as output circuits and power-supply circuits. The
SU-G700 uses a three-section construction with partitions installed between the
circuit blocks according to the signal level handled. This eliminates
interference between circuit blocks, thus achieving clear sound quality. Also,
the chassis rigidity due to this construction suppresses the vibration of
electrical parts, thereby suppressing deterioration in sound quality.

Optimally Activated Circuit System

The Optimally Activated Circuit System allows the operation
of various digital modules to be stopped – such as those used for display,
analogue and digital interfaces – to minimise the noise generated when music is
playing.

Battery Driven Clock Generator

The best power supply for delicate circuitry such as the
clock generator in new amplifiers is one entirely isolated from any noise or
fluctuations in the mains supply. Technics has extensive experience in power
supply isolation using batteries. This technology creates ultra-low-noise
pre-amplifier stages.

High-quality Analogue Circuit

Analogue input is converted with high precision to a digital
signal by the high quality 192-kHz/24-bit A/D converter [Burr-Brown PCM1804
(Texas Instruments)], so the high-purity sound reproduction capability of the
full-digital system can be maximised in playing back analogue sources.
High-definition switching relays are used for signal switching.

Low-noise PHONO Input

The PHONO input achieves low noise by using a differential
parallel connection configuration of a first-stage, low-noise FET. In addition,
four-level gain adjustment enables selection of the best gain according to the
cartridge output. This enables optimal playback of high-grade analogue recorded
sound sources tailored to the user’s environment.

Class AA Headphone Amplifier

The SU-G700 uses a Class AA headphone amplifier with
separate amplifier circuits for voltage amplification and current amplification
of the audio signal. The voltage is amplified by a high-grade operational
amplifier, the current is amplified by an operational amplifier with high current-supply
capability, and the high-grade PWM signal output from the JENO Engine is
converted to analogue with high precision, thus enabling headphones to be
ideally driven. This makes it possible to reproduce music with low distortion
and a wide frequency range no matter what the load impedance of the headphones
is.

Voltage amplification is performed without any load current
so the input signal is faithfully amplified.

The necessary current is supplied to the load according to
the output voltage of the voltage amplifier.

High-rigidity Aluminium Cabinet

The High-rigidity Metal Double Chassis features a
steel-plate inner chassis and a steel-plate outer chassis to reduce vibration
and noise that degrade the purity of sound.

To support heavy parts and components and lower the centre
of gravity for improved stability, the inner chassis is made of a 1.2-mm-thick
plate. The bottom surface of the cabinet is a 2-mm-thick steel plate. This
improves the vibration damping performance and achieves a low centre of gravity.
The front panel is made of a 7-mm thick aluminium plate to resist the effects
of electromagnetic noise.

Accurate Digital
Technology
JENO Engine (Jitter Elimination and Noise-shaping
Optimisation)

LAPC (Load Adaptive Phase Calibration)

High-speed Silent Hybrid Power Supply

Battery Driven Clock Generator

High-rigidity Metal Double Chassis

Noiseless Signal
Technology
Digital Noise Isolation Architecture

Optimally Activated Circuit System

Technics Definitive
Design
High-rigidity Cabinet

Three-section Configuration

FTC Output Power
70 W + 70 W (1 kHz, T.H.D. 0.5 %, 8 Ω, 20 kHz LPF)

140 W + 140 W (1 kHz, T.H.D. 0.5 %, 4 Ω, 20 kHz LPF)

Input Sensitivity /
Input Impedance
LINE 200 mV / 22 kΩ, PHONO (MM) 2.5 mV / 47 kΩ

Frequency Response
LINE 5 Hz – 80 kHz (-3 dB, 8 Ω),

PHONO (MM) 20 Hz – 20 kHz (RIAA DEVIATION ±1 dB, 8 Ω),

DIGITAL 5 Hz – 90 kHz (-3 dB, 8 Ω)

Load Impedance
4 – 16 Ω

Analogue Input
Terminal
LINE x 2 (LINE1 IN, LINE2 IN / MAIN IN) , PHONO (MM) x 1

Digital Input
Terminal
Coaxial Digital x 2, Optical Digital x 2, USB-B (PC)

Analogue Output
Terminal
PRE OUT x 1, LINE OUT x 1 (ANALOGUE SOURCE ONLY)

Headphone Output
Yes

USB-DAC (USB-B)
USB Audio Class 2.0, Asynchronous Mode

Support Codec
DSDYes (2.8224 MHz, 5.6448 MHz, 11.2896 MHz)
PCMYes (32, 44.1, 48, 88.2, 96, 176.4, 192, 352.8, 384 kHz /
16, 24, 32 bit)

Power Supply
AC120 V, 60 Hz

Power Consumption
85 W

Dimensions (W x H x
D)
430 x 148 x 428 mm

(16 15/16 x 5 13/16 x 16 27/32 in.)

Weight
Approx. 12.3 kg

(Approx. 27.2 lbs)

Accessories
Remote Control, AC Cord, Owner’s Manual