KENWOOD D-3300P
¥ 160,000 (released in 1986)
Commentary
A CD player equipped with a digital output to enable digital transmission to external D/A converters in order to take advantage of the quality of light.
It is equipped with optical digital and coaxial digital outputs so that it can be output as digital.
The coaxial output uses a pulse transformer for electrical isolation between devices to prevent audio signal degradation due to noise generated in the earth loop.
It is also possible to turn off the power supply for the D/A converter and analog section that are not required during digital transmission.
It is equipped with a multi-insulation system with the theme of accurately tracing the pit without transmitting disturbance to the pickup.
First of all, an approximately 1 kg aluminum die-cast integrally molded mount is adopted for the base part supporting the mechanism to suppress external vibration transmitted to the chassis, clarify the grounding point of the mechanism, and improve the mounting accuracy of the mechanism. In addition, the mechanism itself is mounted using a special elastic insulator method, and vibration isolation materials are used for the main parts of the mechanism to further strengthen the vibration isolation structure.
In addition, coil springs and a Howbrid insulator made of an elastic body are used to support the pickup to improve the prevention of pick-up movement.
In addition, a highly rigid and heavy cabinet with a 3-mm-thick bottom plate and aluminum extruding is adopted. This ensures high rigidity and reduces sound pressure and floor vibration by weight.
In addition, we have newly developed an insulator that prevents the transmission of vibrations by using a two layered cushion made of a combination of two types of materials, soft and hard.
In addition, it uses a weight stabilizer of 300g each made of a material resistant to vibration.
The signal processing section between the digital and analog signals in the CD player, the data line of the D/A converter section, the mute signal, and the emphasis signal are equipped with photo-couplers. The ground of the digital and analog sections is completely separated.
First of all, by optically transmitting the mute and emphasis control signals, the digital current is returned to the digital GND and grounded. Therefore, the digital noise that enters the high-impedance pattern that draws the mute and emphasis signals is not transmitted to the analog signal system.
In addition, the data line with the highest frequency among the interface system from the digital part to the analog part and with many higher harmonic components is also used for optical transmission. Therefore, dirty current including harmonics is returned to the root of the power supply by a dedicated return circuit and is not transmitted to the analog signal system.
This optical transmission and the independent power supply system of each unit realizes sound with excellent SN feeling.
The D/A converter section is equipped with a digital filter with 4 x oversampling, so that the spectrum of 44.1 kHz, 88.2 kHz and 132.3 kHz is significantly attenuated and transmitted to the D/A converter. Therefore, a slow low-pass filter can be used to improve sound quality.
The D/A converter is equipped with a left / right independent ladder network type D/A converter. In this ladder network type, the conversion accuracy is determined in part by the accuracy of the current source and resistance inside the IC.
With the D-3300P, we have completed a D/A converter integrated circuit in which conversion accuracy is pursued by laser trimming. Since the high-speed D/A converter configuration is capable of handling 4 times over sampling, there is no デグリッジ, and the degrizer circuit, which was indispensable until now, is eliminated.
The low-pass filter uses a 7th-order Butterworth filter with less in-band ripple and excellent phase characteristics, and the FDNR configuration with no active elements in the signal path improves the SN ratio.
When there is a scratch on the disk, the servo gain is instantaneously lowered to 0 level. When the disk passes the scratch, the servo gain is increased. The bit is accurately traced. The TypeIII optimal servo control is adopted. This design is resistant to vibration, scratches and dirt.
The power supply for the analog section, servo system, digital processing system and D/A converter is separated from the transformer winding and independent of each other to eliminate power supply fluctuation caused by mutual interference.
Some CDs have an absolute phase at the time of recording, but when they track down, they become reversed phase. In order to enjoy this CD in positive phase, an invert switch which can invert the phase by 180 ° is installed.
This circuit inverts the phase of the music signal at the stage of digital data, so there is no degradation of sound quality.
It is equipped with functions such as a music calendar that displays track numbers of up to 20 songs, direct selection with 10 keys and plus 10 keys, 4 modes of track play, single play, program play, and time play, auto open that automatically opens the tray when the performance ends, auto close that automatically closes the tray if the tray is left open for 5 minutes, and power on play for timer play.
Wireless remote control is included.
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Model Rating
| Type | CD Player |
| Reading system | Noncontact optical reading |
| Laser | GaAlAs, λ = 780 nm |
| Number of revolutions | Approximately 200 rpm ~ 500 rpm (CLV) |
| Error correction method | Cross interleaved Reed-Solomon code |
| Number of channels | 2-channel stereo |
| Audio Characteristics | |
| Frequency Response (EIAJ) | 1 Hz to 20 kHz |
| Signal-to-noise ratio (EIAJ) | 105 dB or more |
| Dynamic Range (EIAJ) | 97 dB or more |
| Total harmonic distortion factor | 0.001% or Less (THD, 1 kHz) 0.003% or less (EIAJ) |
| Channel Separation (EIAJ) | 115 dB or more |
| Wow & flutter (EIAJ) | Measurement limit (± 0.001% Wpeak) or less |
| Output Voltage (EIAJ) | Fixed output : 2.0 V Variable Output : 0 V ~ 2.0 V |
| Headphone out | 25 mW (32 Ω) with dedicated volume |
| Optical digital output | -15dBm ~ -21dBm (wavelength 660 nm) |
| Coaxial digital output | Coaxial Output : 0.5Vp-p/75 Ω |
| Analog output | 2V(0dB) |
| Multi-Insulation System | |
| Mechanism mount | Die cast mechanism mount |
| Mechanism / Insulator | Vibration isolation mechanism / hybrid insulator |
| High-rigidity and heavy-weight housing | With 3.5 mm Thick Top Plate, 3 mm Thick Bottom Plate Sideboard |
| Insulator | Audio stabilizer + large insulator |
| Circuit Configuration | |
| Servo system | Optimal Servo TypeIII |
| Digital filter | 4 x Oversampling |
| Analog filter | 7th Butterworth FDNR Type Discrete |
| D/A converter | Left and right independent high precision ladder network type |
| <General> | |
| Pwer | 100 VAC, 50Hz/60Hz |
| Power consumption | 16W |
| External dimensions | Width 475x Height 109x Depth 316 mm |
| Weight | 10.8kg |
| Attachment | Wireless Remote Controller RC-P3300D Double pin cord Four audio stabilizers |
| Included : Wireless Remote Control RC-P3300D | |
| Method | Infrared pulse type |
| Pwer | DC3V (Dry Batteries SUM-3 Type, 2 Used) |
| Maximum external dimensions | Width 68x Height 157x Depth 18 mm |
| Weight | 115g (including dry batteries) |