SONY CDP-R3
¥ 300,000 (around 1988)
Commentary
The R series CD player was developed using the same technology as the separate type CDP-R1a and DAS-R1a.
It uses a center mechanical mounting system in which the mechanical deck is placed in the center of the chassis, which is least affected by external vibration. In addition, the mechanism is equipped with a high-rigidity stable-lock mechanism.
The Stay-Lock Mechanism eliminates rattling by reducing the size of the components by eliminating excess projections from the components and assembling these components into a mutually constraining structure. In addition, the overall short span design greatly improves vibration resistance and strength against twisting and bending. On top of this, the G base unit and tray are reinforced with glass fiber by adding calcium carbonate of the same composition as marble to the base unit and tray. The G tray, a movable part, is equipped with a tray lock mechanism in which both sides of the tray are fixed to the mechanism block by two lock arms during performance.
In addition to this, the top of the mechanical deck is equipped with a 5 mm thick extruded aluminum stabilizer to increase rigidity, and by placing it close to the disk, it acts as an air damper that vibrates the top plate and effectively reduces sound pressure entering the interior.
The servo circuit is equipped with a GTS servo, which continuously monitors the fluctuation of the pit train on the disk and works to eliminate the rapid fluctuation that the pit train cannot have.
This GTS servo has a feature that mechanical noise is extremely small. In addition, since there is no wasteful response to scratches, sound skipping is difficult, and recovery to the pit string after passing through scratches is good, so the amount of information read from the disk increases.
In addition, by separating and separating the grind line of the servo circuit with a bus bar, the influence on the ground potential of other circuits is greatly reduced, contributing to improved sound quality.
The optical disk drive motor is equipped with a 3-phase BSL (brush & slotless) motor.
The 3-phase BSL motor, which is structurally less susceptible to vibration, eliminates coking (torque pulsation) and improves stability. In addition, the safety margin of signal reading and servo tracking are improved.
The D/A converter uses a pulse D/A converter similar to the DAS-R1a.
A pulse D/A converter uses one current source and one electronic switch and has only two output values, high (current flow) and low (no current flow). And all the intermediate values of audio waveforms are obtained by the time average of the pulse output, which is the spread of the binary output in the time axis direction. Therefore, in principle, the differential non-linear distortion caused by the error of the current source, the glitch and 0 cross distortion caused by the difference in the operation timing of the electronic switch, which are unavoidable in the conventional D/A converter, do not occur.
The Pulse D/A converter achieves a maximum operating frequency of 50 MHz for the master clock and 50 million pulses per second. The Sony Extended Noise Shaping calculation method is used to calculate the pulses, and a high dynamic range is achieved by generating a high-density pulse train.
The CDP-R3 uses two pulse D/A converters in the complimentary service mode to cancel harmonic distortion with auxiliary positive and negative outputs and to increase the S / N ratio by doubling the output current value.
The master clock is placed so close to the pulse D/A converter that it can be said that it is directly attached, and a direct digital sync circuit for rearranging the data on the chip of the pulse D/A converter is mounted. This realizes a clean D/A conversion without jitter.
The characteristics are improved by installing a low-jitter optical output unit.
FB chassis is adopted for the chassis structure.
This chassis is made of metal material of sufficient thickness and strength, and the whole chassis is joined by a frame surrounding the outer circumference and beams before and after passing the front and rear. This structure ensures almost total strength only by this frame and beams.
It is fixed directly on the most neutral beam with low vibration without using any special metal fittings when mounting the mechanism and substrate.
In addition, with CDP-R3, the mass of the block is increased by fixing the large-weight power transformer on the same beam as the mechanical deck with anti-vibration measures. This is combined with the center mechanical mounting method to obtain a good weight balance, which simplifies the vibration moment and prevents the chassis from rotating.
The legs are made of fine ceramic insulators combined with rubber with good braking performance.
A 2-transformer configuration is used for the power supply for digital servo independently and exclusively.
In CDP-R3, two transformers are housed in a single transformer case as a twin core transformer, and two transformers of the same size are arranged side by side to prevent mechanical tuning fork resonance.
The front panel is designed to be as simple as possible, and only the minimum necessary functions related to play operation are arranged. Functions such as program performance are performed by the attached remote control.
In addition to basic operations such as play / stop, the included remote control allows direct selection, program performance of up to 20 songs, shuffle / delete shuffle performance with randomly rearranged songs, repeat performance in 6 modes, etc. It also includes a program bank for storing the order of programmed songs, and a custom index for placing the original index in the desired part of a song.
Equipped with an automatic timer start function that can start playing automatically by combination of external timers.
Model Rating
| Type | CD Player |
| DISK | Compact disc |
| Read method | Non-contact optical reading (using semiconductor laser) |
| Laser | GaAlAs double hetero diode, λ = 780 nm |
| Number of revolutions | Approximately 500 rpm ~ 200 rpm (CLV) |
| Error correction method | Sony Super Strategy Cross interleaved Reed-Solomon code |
| Number of channels | 2 channels (stereo) |
| Frequency characteristic | 2 Hz to 20 kHz ± 0.5 dB |
| Signal-to-noise ratio | 117 dB or more (EIAJ) |
| Dynamic range | 100 dB or more (EIAJ) |
| Total harmonic distortion factor | 0.002% or less (EIAJ) |
| Channel separation | 110 dB or more (EIAJ) |
| Wow and flutter | Below the measurement limit (± 0.001% W. peak) (EIAJ) |
| Output terminal | Unbalanced (pin-jack) : 2.5V/50k Ω Balanced (XLR terminal) : 5V/600 ohm Coaxial Connector : 0.5Vp-p/75 Ω Optical connector : -18dB (emission wavelength 660 nm) |
| Memory | Held for more than 1 month (after power off) |
| Pwer | 100 VAC, 50Hz/60Hz |
| Power consumption | 17W |
| External dimensions | Width 470x Height 125x Depth 410 mm |
| Weight | Approximately 18 kg |
| Included : Wireless Remote Control RM-A1a | |
| Remote control system | Infrared pulse system |
| Pwer | 3 VDC, 2 AA batteries are used. |
| External dimensions | W 67x H 20x D 175 mm |
| Weight | Approximately 110g (including dry batteries) |