Audio Database

The

Pioneer PD-T05
80,000yen(1990 release)

Description
 
The compact disk player which asks the first generation who adopted the turntable scheme.

compact-disk turntable scheme into which it was made to develop from a disk stabilizer is adopted.
It is possible to support a disk all over a turntable from the bottom like an analog player by considering it as a pickup and the structure of installing a spindle motor in the upper portion of a disk.
It is strong on the disk whose moment of inertia of a turntable improves by about 3 times over the past and which has the influence of an extraneous vibration or sound pressure, and curvature by this, and it is possible to suppress an unnecessary oscillation of a disk.

8fs digital filter and the right-and-left independent bit stream digital analog converter are carried in the D-A-conversion part.
This digital analog converter does not have theoretically an occurrence of the nonlinear distortion resulting from the error of an electrical resistor like a multiple bit scheme, or gap of timing of operation, or zero cross distortion. By performing high oversampling called 192fs based on a 3rd [ further ] noise shaper, the influence of a noise shaper is suppressed low.
Moreover, by a 1-bit scheme, all the operations are controlled with the system-clock, and the Jitter of a system-clock affects a performance. In order to avoid the influence, it is made to operate with the same low system-clock (16.93MHz) as the conventional multiple bit scheme.
Moreover, attention is also paid to application and vibration proof and magnetic-shield treatments, such as preparing the independent oscillator circuit, have been performed.

In order to transmit a music signal purely, the direct construction is adopted and shortest-ization of a signal path is realized with arranging main circuitries in a simple & straight along with the fluence of a signal.
Moreover, the center tray design which allotted the pickup mechanism in the center was begun, digital one/servo, and the audio substrate were separated, and the interference in each circuitry is prevented. Furthermore, an analog circuit substrate also ties even an output-terminal with the shortest distance from an input, and is considered as the symmetrical stream composition.
This has eliminated the break-in of the noise by leading about of product-line material, and the interference between circuitries.

The proprietary clean laser pickup is adopted as a pickup, and the power loss of optical system is decreased by reducing optical components, such as a collimator lens. Furthermore, the aberration in an optical path is reduced and the pickup of little distorted signal is enabled.
Moreover, highly precise precision form is realizable by having adopted the engineering plastic body as the body, dividing the pickup body into about 1000 member, and conducting an intensity analysis.
Furthermore, I/V transducing head amplifier is built in the photodetector, and the transmit strong against a disturbance noise is enabled by amplifying for about 200mV order.

Class-A operation FET buffer amplifier is adopted as an audio circuitry, an Output load impedance is lowered and the influence of the load intensity of the amplifier connected etc. is reduced.
Furthermore, by Class-A operation, the variation of the power consumption at the time of an operation was reduced, and the stable waveform transmission is realized.

When highly precise 4 splitting photodetector receives laser light, the phase difference arises between a lead signal and a Yukinobu Ushiro number, and disorder produces it to RF signal. In order to improve this, the Accu Focus system is adopted, and RF signal with little reading error has been acquired by delaying the signal of a lead and making it agree with the signal of the back line by a delay circuit.

The brushless hall motor of starting torque 65 g-cm is carried in the spindle motor. Furthermore, the phi4.5mm very-thick shaft and the rotation performance conjointly stabilized in a load variation strongly are demonstrated.
Moreover, the silence linear motor servo mechanism in whom a quiet and smooth operation is possible is employed as a pickup drive, and the quick access is enabled.

In order to protect an optical mechanism from an extraneous vibration, the lamisert Mechanism-base is adopted.
This piles up two steel plates, is what carried out molding by the special resin, and also is suppressing the improvement in a periodic-damping property, and the occurrence of a magnetic distortion by giving a copper plating.
Moreover, this Mechanism-base has mounted special rubber and a spring on a mechanism chassis through the coaxial-ized coaxial suspension,the extraneous vibration from a chassis is intercepted by mounting the turntable base through a coaxial suspension similarly, and it being alike, respectively, and considering it as a flow and a structure.

The newly developed multilayer structure honeycomb chassis is adopted as a chassis.
Greatly, internal losses are the steel plate excellent in the electromagnetic shielding, and the thing which piled up cushion material, reduce an unnecessary oscillation according to the outstanding vibration suppression effect based on the honeycomb chassis by BMC (Bulk Molding Compound) of a high rigidity, and are also suppressing the reflection of the sound from a floor low.
Furthermore, by k which installs the 5th insulator in the chassis central part at an insulator, vibration proof and a weight balance are maintained and the center mechanism is supported.

The twin power transformer which made it become independent digital one/object for servo circuitries, and for analog circuits is carried in the power-source part.
Furthermore, the by filer volume is adopted as the transformer for audio circuitries, by raising the degree of balance of installation of an Output load impedance or an inductance, the power source by the side of + and - is supplied on the same requirements, and a transparent feeling and a low-pass feeling of a drive are improved.
Moreover, the power circuit had employed 4 part 11 regulator, carried out the independent rectification of the four parts of a servo/digital one, a servo drive, + of an audio, and -, and has eliminated the cross interferencee.

The clean microcomputer which operates only when the operation key is pressed is carried, and the scanning noise is canceled.

Digital one / analog out change-over switch is carried.

The display-deviceoff switchpoint is carried in consideration of the scanning noise occurrence at the time of display-device lighting.

High Attached

Rating of a mode
Form Compact disk player
Pickup 3 beam semiconductor laser scheme
Frequency characteristic 2Hz - 20kHz
SN ratio (EIAJ) 115dB or more
Dynamic range (EIAJ) 99dB or more
Channel separation (EIAJ) 110dB or more
Wow and flutter (EIAJ) Below a limit of measurement (±0.001%W.PEAK)
THD (EIAJ) 0.0017% or less
Output voltage 2.0Vrms
The number of channels Two channels (stereo)
Digital output Coaxial output: 0.5 Vp-p/75ohm
Optical power: -15dBm--20dBm (wavelength of 660nm)
Power source AC100V, 50Hz/60Hz
Power consumption 20W
Dimensions Width 420x height 130x depth of 330mm
Weight 10.0kg
Adjunct Remote control