SANSUI CD - α 907i

Commentary

A CD player with Sansui's technology.

Equipped with SANSUI's original Super SF (solid & flex) mechanism.
In this mechanism, a copper clad material, in which 40 μ m copper plates are molecularly bonded on both sides of a single steel plate, is adopted for the mechanical chassis and play chassis, and excellent vibration damping characteristics and shielding characteristics are obtained. In addition, a floating suspension system is adopted for the play chassis, and it is mechanically floated from the mechanical chassis by coil spring and NR damper to block the influence of internal resonance and external vibration.

Newly developed exclusive brushless and slotless motor is adopted for the spindle motor, and the Center shaft has a 3 φ high-precision finish.

A 3-beam pickup is used for the pickup part.
A die-cast base is used for this pickup, and excellent torless performance is obtained by suppressing vibration.

The servo circuit employs a dynamic servo system that reduces the load on the servo under normal conditions. When the disk is dirty or damaged, the system responds instantly, providing a highly responsive and stable tracing capability.

The digital filter employs a 4 x over-sampling digital filter that increases the sampling frequency from 44.1 kHz to 176.4 kHz, a 4 x increase, and reduces high-order harmonic noise in the music signal and sampling frequency.
This digital filter has excellent phase characteristics, cutoff characteristics, group delay characteristics, and extremely low ripple in the audio band. Therefore, the load on the analog filter is reduced, and sufficient filter effect can be obtained by using a low-order low-pass filter with simple and gentle attenuation characteristics. As a result, phase disturbance and distortion in the music signal band, which were generated by conventional high-order analog low-pass filters, are greatly reduced.

The D/A converter uses an independent twin D/A converter for both left and right.
The D/A converter is equipped with a high-precision ladder -type D/A converter capable of high-speed serial data processing to eliminate glitches (noise) during D/A conversion. By using this high-speed, high-precision D/A converter in a twin configuration with independent left and right channels, phase difference and crosstalk between channels are minimized, and sound quality is improved. In addition, a cross-fine circuit is adopted to suppress 0 cross distortion that occurs in minute signal regions.
In addition, the CD - α 907i uses a high-speed photoisolated system to eliminate the influence of digital noise on the analog system.

SANSUI's unique α -X balanced circuit is used in the analog amplifier section, and it is composed of 4 discrete amplifiers. In the α -X balanced circuit, the signal system is independent from ground, so that noise and distortion including digital noise are eliminated, and high purity sound is obtained.

Equipped with balanced output terminal.

The power supply has a 2-transformer configuration with separate transformers for analog and other digital, servo and display systems to eliminate adverse effects of the power supply to the audio section.
In addition, low impedance and high speed have been achieved by the stabilization circuit with improved accuracy.

The master clock system, which operates the digital signal processor, digital filter and D/A converter at the same clock, eliminates harmful beats caused by clock phase shifts and clock frequency differences when using multiple clock oscillators.


Solid & anti-flux chassis of copper plating specification is adopted for the chassis structure.
By installing shields and separators for high rigidity in the servo system, digital section and analog section, unnecessary vibration is eliminated, and interference between each section and external electromagnetic noise is prevented.

5-point support CF5 insulator with optimum load balance is adopted for the leg part to suppress external vibration.
The CD - α 907i uses a combination of a brass insulator and a compliant special insulator.

Equipped with coaxial digital output terminal.
The digital ON/OFF switch on this jack prevents the digital signal from leaking outside when Digital Out is not used.

The AC line is equipped with a line filter to prevent the outflow of digital noise.

Equipped with CD centering mechanism to accurately mount CD on turntable.

Uses a very thick power cord with polarity display.

It is equipped with functions such as Music Scan, 3-mode repeat, and 20-track random program.

It has a large display with a music calendar of 20 songs.

Equipped with auto-space function.

Wireless remote control is included.

Model Rating

Type	CD Player
Reading system	Noncontact optical
Pickup type	High-precision 3-beam semiconductor laser system
Number of revolutions	200 ~ 500 rpm
Number of channels	2 Channel
Sampling frequency	44.1kHz
Number of quantization bits	16-bit linear
Frequency characteristic	4 Hz to 20 kHz
Harmonic distortion factor	0.002% or Less (1 kHz)
Dynamic range	98 dB or more
Wow and flutter	Measurement detection limit or less
Signal-to-noise ratio	108 dB or more
Output voltage	Normal:2V Balance:2V
Rated power consumption	30W
External dimensions	Width 448x Height 98x Depth 405 mm
Weight	10.5kg
Attachment	Wireless Remote Control