Pioneer PD-T06 - Audio Database

• Pioneer PD-T06

• ¥ 120,000 (released in 1993)

Commentary

A turntable CD player with Legato Link Conversion.Legato Link Conversion is included to reproduce sound above 20 kHz, which is cut off in CD, and to play more natural music.In order to improve pulse response, this circuit connects music signal data recorded on a CD every 22.7 μ sec with a smooth function curve suitable for reproducing the frequency components of musical instruments. This makes it possible to reproduce a waveform close to the original music signal without unnecessary ringing (waveform disturbance).In addition, by estimating the original signal before recording based on the signal recorded on such a CD, it is possible to reproduce the sound of 20 kHz or higher according to the 1/f attenuation characteristic, and the reproduced sound is extremely natural and smooth in the sense of hearing.The mechanism uses a CD turntable system to reduce unnecessary vibration of the disk.By moving the pickup and spindle motor from the lower part of the disk to the upper part and supporting the disk on the entire surface of the turntable, it is resistant to external vibration, sound pressure, and warped disks, and reduces unnecessary vibration of the disk.In addition, it is resistant to load fluctuations and realizes stable rotational performance.The D/A converter is equipped with an originally developed high-speed pulse flow D/A converter.In this D/A converter, the noise shaper operates at a very high oversampling frequency of 384 fs, enabling fine sampling and greatly reducing the noise floor due to requantization. In addition, the noise shaper can be used in second and lower orders, reducing the effect of out-of-band noise on sound quality.In addition, the effect of jitter is reduced by operating the master clock at a low clock frequency of 16.93 MHz.Main circuits are arranged simply and straight along the signal flow, and direct construction is adopted to minimize the signal path. In addition to the center tray design with the pickup mechanism in the center, digital / servo and audio boards are separated independently to prevent mutual interference.In addition, a sealed PCB (double-sided substrate) is used for the audio substrate, providing an excellent shielding effect against noise jumping from the digital system to the audio system.In addition, by connecting the input terminal to the output terminal with the shortest distance and using a symmetrical configuration, the intrusion of noise caused by the routing of wiring materials and mutual interference of circuits are eliminated.A clean laser pickup developed in-house is used in the pickup section.This pickup reduces the power loss of the optical system by reducing the number of optical parts such as the collimator lens, and also reduces aberrations in the optical path, making it possible to read clean signals with less distortion.In addition, an engineering plastic body is used for the body, and by dividing the pickup body into approximately 1000 elements and performing strength analysis, a high precision and precise shape is realized.In addition, the built-in I/V head amplifier in the photodetector, combined with the Accu-Focus system that reduces signal reading errors, reduces jitter caused by reading errors and disturbance.Equipped with an Accu-Focus system that reduces signal reading errors.When receiving a laser beam, a high-precision four section photodetector generates a phase difference between the preceding signal and the following signal, resulting in disturbance of the RF signal. In order to improve this, a delay circuit is used to delay the preceding signal and match it with the following signal to obtain a high-output RF signal with error.The audio circuit uses a class-A FET buffer amplifier to reduce the output impedance and minimize the influence of the load of the connected amplifier. In addition, the class-A operation reduces the fluctuation of power consumption during operation and enables stable waveform transmission.The spindle motor is equipped with a brushless Hall motor with a high starting torque of 65g ・ cm. Combined with a thick φ 4.5 mm shaft, it is resistant to load fluctuations and provides stable rotational performance.In addition, the pickup drive uses a silent linear motor servo eye that is quiet and smooth in operation to realize smooth access.Lamisert mechanical base is adopted, and vibration damping characteristics are improved by the structure in which two steel plates are overlapped and molded with special resin, and generation of magnetic strain is suppressed.In addition, the mechanical base is mounted on the mechanical chassis via a coaxial suspension made of special rubber and springs, and by adopting a float structure, unwanted vibrations transmitted from the chassis are shielded.The multi-layered honeycomb chassis is made of BMC (Bulk Molding Compound) with high internal loss and high rigidity. Steel plates and cushioning materials with excellent electromagnetic shielding are layered on top of the honeycomb chassis. The excellent damping effect reduces unwanted vibration.In addition, a large honeycomb insulator that reduces the reflection of sound from the floor is adopted. In addition, a fifth insulator is installed in the center of the chassis to increase the vibration resistance of the chassis and support the center mechanism.The power supply section uses twin power transformers for digital / servo circuits and analog circuits.In addition, a discrete push-pull power supply is used for the audio circuit, and a bifilar winding is used for the audio transformer to improve sound quality.The power supply circuit is a 5-part, 12-regulator. Servo / digital, servo drive, D/A converter D/A converter and audio + and - to prevent interference.Scanning noise is reduced by adopting a clean microcomputer that operates only when the operation key is pressed.Also equipped with a display off switch to prevent the generation of scanning noise when the display is turned on (for backup)Equipped with a digital / anlogout changeover switch (for backup).

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Model Rating

Type	CD Player
Pick-up	Three beam semiconductor laser system
Frequency characteristic	2 Hz to 20 kHz
Signal-to-noise ratio (EIAJ)	115 dB or more
Dynamic Range (EIAJ)	99 dB or more
Channel Separation (EIAJ)	110 dB or more
Wow & flutter (EIAJ)	Measurement limit (± 0.001% W. PEAK) or less
Harmonic distortion factor (EIAJ)	Not more than 0.0017%
Output voltage	2.0Vrms
Number of channels	2 channels (stereo)
Digital output	Coaxial Output : 0.5Vp-p/75 ΩOptical output : -15dBm ~ -20dBm (wavelength 660 nm)
Pwer	100 VAC, 50Hz/60Hz
Power consumption	17W
External dimensions	Width 440x Height 130x Depth 330 mm
Weight	10.0kg
Attachment	Wireless Remote Control