Review: Technics SU-C550 All-in-one network CD stereo amplifier

All-in-one network CD stereo amplifier Technics SU-C550 mounted under perfect HiFi harmony and elegant in a truly essential compact design.

Jitter is a major cause of distortion in digital systems, and is caused by incorrect timing on master clocks used in digital-to-analog conversion. To eliminate sound degradation caused by jitter, Technics has developed an original jitter reduction circuit, comprising a clock generator in the noise modeling system to reduce jitter in the low frequency range and a high-precision sample frequency converter to suppress jitter in the high frequency range. Therefore, it reduces jitter in an ideal way across the entire frequency range. This works with an original, high-precision PWM (Pulse Width Modulation) conversion circuit, optimizing noise modeling speed, grade error and recanting, and PWM gradation, in order to convert high-resolution signals to PWM without causing any damage to the dynamic range. These new technologies allow new Technics digital amplifier designs to reproduce the natural and delicate nuances of music.

Dual power supply circuit system
Regular power supplies use a transformer to supply power to the amplifier, CD unit, and digital circuits, so if there is any load fluctuation or if noise occurs in a circuit, other circuits are affected, resulting in degradation of sound quality. This power supply system includes independently installed switching mode power supply circuits for the amplifier and other circuits, eliminating mutual interference, thus reducing degradation of sound quality caused by noise or power supply fluctuations.

LAPC is an unique speaker load adaptive technology from Technics. With speakers connected to the amp, it analyzes the frequency amplitude phase characteristics and applies digital signal processing to provide the optimal impulse response.

Battery-powered clock generator
In digital audio, the improvement in the accuracy of the watch, which serves as a reference for operation, is extremely important to achieve high sound quality. But the power supply noise for the clock circuit can become a problem. Technics employs the battery-powered clock circuit that was successfully used in our analog amplifiers in the past. As a result, the accuracy of the watch was improved, making a more defined sound presence and excellent spatial expression.

Digital noise isolation architecture
The Technics SU-C550 receives audio signals from various digital content devices, such as NAS, PC, USB memory devices, and digital interfaces. Because many of the digital content storage media is designed for PC use, low noise, which is required for pure audio playback, was not the main design concern. To handle these often noisy sources, the Technics SU-C550 isolates interfaces so that these media exclude external electrical interference, and also employs a jitter remover (includes JENO-LSI), thus offering clear, stable sound, free of noise and distortion.

Wi-Fi capability
The connection is possible to a home network via a LAN cable or a wireless configuration (IEEE802.11a/b/g/n). The built-in Wi-Fi feature allows you to easily connect to the network without routing a LAN cable, even if your PC or broadband router is configured in another room. Photo:Technics

Bluetooth capability®
The Bluetooth® function allows easy transmission from a Bluetooth ® device.

TIDAL, Spotify and vTuner compatible
In addition to DLNA and USB playback, TIDAL, Spotify* Connect and vTuner are supported. For vTuner, use the Technics Music app to select stations and listen to a wide variety of broadcasts.

Accurate Digital Technology

JENO Engine (Jitter Elimination and Noise-shaping Optimisation)
LAPC (Load Adaptive Phase Calibration)(w/o calibration function)
Battery Driven Clock Generator

Noiseless Signal Technology

Digital Noise Isolation Architecture

Output Power

20 W + 20 W (1 kHz, T.H.D. 0.5 %, 8 , 20 kHz LPF)
40 W + 40 W (1 kHz, T.H.D. 0.5 %, 4 , 20 kHz LPF)

THD+N

0.05 % (1 W at 1 kHz, 8 , 20 kHz LPF)

Load Impedance

4 Ω – 16 Ω 

Digital Input Terminal

Optical Digital, USB-A, USB-B

Disc Compatibility

Audio CD, CD-R/CD-RW (CD-DA, Discs recorded and finalised on recording devices)

USB-A

iPod/iPhone/iPad

Yes

Support Codec

WAVYes (32, 44.1, 48, 88.2, 96, 176.4, 192 kHz / 16, 24 bit)

FLACYes (32, 44.1, 48, 88.2, 96, 176.4, 192 kHz / 16, 24 bit)

DSDYes (2.8224 MHz, 5.6448 MHz)

AIFFYes (32, 44.1, 48, 88.2, 96, 176.4, 192 kHz / 16, 24 bit)

ALACYes (32, 44.1, 48, 88.2, 96, 176.4, 192 kHz / 16, 24 bit)

AACYes (32, 44.1, 48, 88.2, 96 kHz / 16-320 kbps)

WMAYes (32, 44.1, 48 kHz / 16-320 kbps)

MP3Yes (32, 44.1, 48 kHz / 16-320 kbps)

USB-DAC (USB-B)

USB Audio Class Specification

USB Audio Class 2.0, Asynchronous Mode

Support Codec

DSCYes (2.8224 MHz, 5.6448 MHz)

PCMYes (32, 44.1, 48, 88.2, 96, 176.4, 192 kHz / 16, 24, 32 bit)

DLNA Support Codec

WAVYes (32, 44.1, 48, 88.2, 96, 176.4, 192 kHz / 16, 24 bit)

FLACYes (32, 44.1, 48, 88.2, 96, 176.4, 192 kHz / 16, 24 bit)

DSDYes (2.8224 MHz, 5.6448 MHz)

AIFFYes (32, 44.1, 48, 88.2, 96, 176.4, 192 kHz / 16, 24 bit)

ALACYes (32, 44.1, 48, 88.2, 96, 176.4, 192 kHz / 16, 24 bit)

AACYes (32, 44.1, 48, 88.2, 96 kHz / 16-320 kbps)

WMAYes (32, 44.1, 48 kHz / 16-320 kbps)

MP3Yes (32, 44.1, 48 kHz / 16-320 kbps)

Headphone Output

Yes (Ø3.5 mm)

Ethernet Interface

LAN (100 Base-TX / 10 Base-T)

Wi-Fi

IEEE 802.11a/b/g/n, 2.4 GHz Band (1-13 Channel),
5 GHz Band (36, 40, 44, 48 Channel)

AirPlay

Yes

Bluetooth® (Support codec)

Yes (AAC, SBC)

TIDAL / vTuner / Spotify

Yes/ Yes / Yes

Power Supply

AC220-240 V, 50 Hz / 60 Hz

Power Consumption

50 W

Dimensions (W x H x D)

360 x 91 x 258 mm

Weight

Approx. 3.9 kg

Accessories

Remote Control, AC Cord, Owner’s Manual, Network Connection Guide, Batteries for Remote Control

Technics SU-C550 Troubleshooting

Cannot connect to the network
• Confirm the network connection and settings.
• If the network is set to be invisible, make the
network visible while you set up the network
for this unit or make a wired LAN connection.
• This system’s Wi-Fi security supports WPA2.
Your wireless router must therefore be
WPA2 compatible. For details on the security
supported by your router and how to change
the settings, please refer to the operating
instructions or contact your internet service
provider.
• Make sure that the multicast function on the
wireless router is enabled.
• Depending on the router, WPS button may not
work. Try another connection method.
• The wireless LAN environment or radio
interference in your area may cause connection
problem. In this case, try another connection
method. If the problem persists, make a wired
LAN connection.
• While the AC mains lead is disconnected, the
LAN cable must be connected or disconnected

Playback does not start.
The sound is interrupted.
• The station that does not broadcast cannot be
played back. (It will be skipped or return to the
list.)
• Internet Radio may not be played back properly
depending on the network condition.
• Depending on the internet connection
environment, the sound may be interrupted or
it may take some time to play back.
• Internet Radio is an audio broadcasting service
transmitted via the Internet. Depending on the
broadcaster or condition of the transmitting,
the sound quality may vary.
Cannot display the information properly.
• Track names, station names, etc. which are
managed by vTuner/Spotify may not be
displayed properly.

The PC does not recognise this unit.
• Check your operating environment.
• Restart the PC, turn this unit to standby and
on, and then reconnect the USB cable.
• Use another USB port of the connected PC.
• Install the dedicated USB driver if using a PC
with Windows.