SONY CDP-337ESD

Commentary

This CD player was developed based on the design philosophy of the reference CDP 557 esd.

The digital filter uses a newly developed IC (CXD1144) with an 8 x oversampling 18-bit digital filter.
This newly developed digital filter has an extremely high-order 293 order preserving in salt capability, and achieves an in-band ripple characteristic of ± 0.00001 dB and an attenuation of 120 dB or more in the stopband. As a result, the generation of echo components caused by ripple can be suppressed to a negligible level. In particular, the reproducibility of the rising of a single sound of piano is improved.
In addition, by increasing the sampling frequency from 44.1 kHz to 352.8 kHz by 8 times over sampling, the quantization noise in the audio band can be greatly reduced. At the same time, the distance between the music signal component and the unnecessary high-frequency component has been expanded to 332.8 kHz. Thus, the cutoff characteristics of the low-pass filter after D/A conversion can be relaxed, further improving the group delay characteristics.

The D/A converter is equipped with a Staggered 4D/A converter system to improve the resolution of the 16-bit D/A converter.
This method uses four D/A converters, two for each L/R channel, for staggered operation. These converters support sampling frequencies up to 352.8 kHz and enable high-speed, high-precision 8 x D/A conversion.

A newly developed aluminum die-cast base unit is adopted for the base unit which is the base of the optical system mechanism, and the trace stability is improved by effectively suppressing unnecessary vibration. In addition, the entire base unit is made into a floating structure by double suspension containing high viscoelastic gel rich in vibration absorption, and the effect of external vibration is strictly eliminated.

The pickup section has no transmission mechanism such as gears, and uses a linear motor tracking mechanism that enables high-speed access with extremely quiet operation.

A mechanical block, which tends to be a source of vibration inside the player, is attached to a G (Gibraltar) base and then firmly fixed to the chassis. This G base material contains calcium carbonate with the same composition as marble, added to a special resin and reinforced with glass fiber. This material is the same as that used in the ES series amplifier chassis. It has the features of extremely high rigidity and excellent vibration damping characteristics, and it is easy to tune from the shape and acoustic aspect.
This reduces the transmission and resonance of vibrations that degrade sound quality.

In consideration of the effect of sound pressure radiated from the speakers, a damper made of special rubber material is installed in the opening of the front panel where the disk tray is stored to improve airtightness when the tray is stored, thereby blocking even slight air vibrations.

The chassis uses a high-rigidity double structure metal chassis with structure equivalent to CDP-557ESD.
In addition, the W chassis with a laminated structure consisting of two plates of sufficient thickness is adopted for the bottom plate, and rigidity and vibration control are thoroughly enhanced.

It uses a taper chucking method that absorbs the eccentricity due to the error of the center hole of the disk and keeps it within a negligible range.

The servo circuit is equipped with S Servo II, which is an improved version of S Servo.
The operating principle of the S servo is that the RF-IC detects signal drop-out caused by scratches or dirt, calculates the timing of the next drop-out based on the rotation cycle of the disk, and optimally controls the servo amount of both tracking and focus servo circuits just before the drop-out to minimize the occurrence of errors.
The S Servo II performs even more precise predictive control of the servo amount. The prediction time accuracy is improved from 1/8,000 second to 1/10,000 second. Moreover, by supporting CLV (constant linear velocity), this accuracy is maintained at any position inside and outside the disk. Compared to the method in which the servo amount is controlled after the drop-out occurs, the trace stability is improved and the disturbance of the servo current is greatly reduced.

The analog circuit has a twin-mono configuration that follows the signal flow, and phase shift and mutual interference between channels are eliminated from the root. In addition, the circuit configuration has been greatly simplified by incorporating digital filters.
In addition, the MOS gate transfer method is adopted for digital data transmission to the analog system to prevent data current from mixing into the analog system ground, thereby eliminating factors of sound quality degradation.

The power supply section is composed of 11 independent stabilized power supplies with separate windings for each signal system to eliminate mutual interference between circuits.

Uses carefully selected parts such as an ES board that prevents unnecessary capacitance.

It is equipped with a digital processing soft muting circuit, and it prevents click noise by instantly muting when the performance stops or poses are operated.

It has two digital outputs, coaxial and optical, with a time axis correction latch located just before the coaxial digital output to more strictly eliminate the fine jitter component.
Equipped with a digital / analog output changeover switch to prevent mutual interference.

There are two analog outputs, fixed and variable.

Equipped with line-out volume for headphone output as well.
These volumes can be controlled by remote control and are motor-driven when the volume is adjusted by remote control.

A custom file function is included as a new function.
This function allows the CD player to store up to 226 titles of music information and messages input by the listener for each disc. Each time a disc is replaced, the CD player automatically identifies which disc it is, recalls the memory, displays messages for each disc, and plays the disc according to the performance information.
Custom files have three functions : disk memos, custom indexes, and program banks. You can file disk notes and either custom indexes or program banks.
Disk Memo allows you to enter your own message up to 10 characters per disk.
The custom index can be set up to a maximum of 6 points per disk. To set the index, press the FILE button during playback to specify the point.
The program bank can store up to 20 program performance functions.
By memory backup, stored contents are retained even when power is turned off.

Equipped with a program edit function, editing program can be done for each A/B side of the tape at one time.

It has a delete shuffle function that allows you to shuffle and play only your favorite songs.

Equipped with 6-mode repeat of 1 song / whole song / part (remote control only) / program / shuffle / custom index.

It is equipped with a time keeper function with the next display to know the next program performance music.

Equipped with auto space / auto pause function.

Equipped with Music Search.

Wireless remote control is included.

Model Rating

Type	CD Player
Reading system	Non-contact optical reading (using semiconductor laser)
Laser	GaAlAs double hetero diode
Number of revolutions	200 ~ 500 rpm (CLV)
Playing speed	1.2m/s ~ 1.4m/s (constant)
Error correction method	Sony Super Strategy Cross Interleaved Read-Solomon Code
Number of channels	2 Channel
Frequency characteristic	2 Hz to 20 kHz ± 0.3 dB
Total harmonic distortion factor	0.0025% or less (EIAJ)
Dynamic range	97 dB or More (EIAJ)
Wow and flutter	Below the measurement limit (± 0.001% W. peak) (EIAJ)
Output level	2 vrms (MSB, Fixed) 2 Vrms ~ 0 V (MSB, Variable)
Digital output	Coaxial : 0.5Vp-p/75 Ω Optical : 660 nm (emission wavelength)
Headphone output level	28 mw (32 Ω)
Power consumption	22W
External dimensions	Width 430x Height 125x Depth 375 mm
Weight	12.5kg
Attachment	Wireless Remote Control RM-D650