What is stereo?




There are now two system of high fidelity, monophonic (monaural) and stereophonic. Monophonic is a system that starts from one microphone and is fed through a single high fidelity set. Stereophonic is a double system. Two separate microphones are placed at different sides of the orchestra and two different systems are used to keep the two signals or channels separated. Two separate speakers are used, placed on different sides of you room. Stereo is much like 3-D photography, two slightly different sound reach your ears giving you a new dimension in sound.




H.H. Scott '59





Pioneer P-D1 (1983)


The P-D1 Compact Disc Player: Proof of Pioneer leadership in laser and audio technology.
The Compact Disc represents a radical departure from conventional analogue forms of music reproduction. The sound quality of a CD player relies on more than just the digital circuity. Analogue circuitry - a series of stages after the D/A converter - handles music in its original analogue audioform. 
The very best analogue technology is needed to ensure that distortion does not creep in at this final stage. That's why for the P-D1, we,ve used our finest audio circuitry built around select parts such as our polypropylene capacitors. Pioneer's unmatched reputation for excellence in analogue audio technology is your guarantee of incomparable sound quality.


Pioneer microelectronics
When the CD player reads the microscopic pits that store musical information, it must do so at high speed and with perfect accuracy. To keep the pickup on track. We’ve  used three sophisticated servo systems -  a focus servo, a tracking servo and a spindle servo.
The focus servo keeps the laser beam focused on the reflective surface of the CD by moving the objective lens toward or away the focus of the laser beam to follow  the centre line of a track by monitoring adjacent tracks. The spindle servo keeps the linear velocity of the disc constant by continuously adjusting the speed of the spindle motor.
All of this advanced Pioneer electronics ensures the tracking remains smooth, precise and free of transfer error.

Best quality audio circuitry
The sound quality of a CD player relies on more than just the digital circuitry. Analogue circuitry - a series of stages after the D/A converter - handles music in its original analogue audio  form. The very best analogue technology is needed to ensure that distortion does not creep in at this final stage. That's why for the P-D1, we've used our finest audio circuitry, built around select parts such as out polypropylene capacitors. Pioneer's unmatched reputation for excellence in analogue audio technology is your guarantee of incomparable sound quality.


Super Specifications
You have to hear the sound of the Compact Disc System to believe it. Noise and distortion are, for all practical purposes. Nonexistent. Frequency response and channel separation are dramatically increased. Dynamic range is a 50% improvement over conventional analogue systems, very nearly reproducing the dynamics of a live performance. The specifications are nothing short of electrifying:
Dynamic range is over 90 dB
Signal-to-Noise ratio is better than 90 dB
Harmonic distortion is less than 0,006%
Channel separation is greater than 90 dB
Frequency Response is flat within ±0,5 dB from 5 Hz to 20 kHz
Wow and flutter are unmeasurable by state-of-the-art.  Instrumentation

Convenient features of the P-D1
In addition to musical information, a Compact Disc contains a digitally- encoded table of contents  and indexes for instant cueing. This makes possible the following convenient functions:
Random Search - lest you start playback from any desired point on a disc. Select by means of specific track (selection) or by means of elapsed time ( from start of the track)
Phrase Play - when a phrase number is entered playback starts automatically from the beginning of any phrase within a single track.
Skip - lest you backtrack to the beginning of the current track (selection) or skip ahead to the next one.
Index Scan - lets you hear the first 7 seconds of every track (selection) on a disc in succession
Music Repeat/One-Side Repeat - permit repeat of any track (selection) and repeat of the whole side of a disc, respectively.
Programmed Function - lets you hear any number of tracks (selection) up to 16 in any order you desire.
Status Indications - when the Total key is touched, the total number and total play  time of selections you have programmed are displayed. Touch the "PGM Check" key to find out the track number of the current selection and the total time of selections yet to be played.
P-D1 Specifications
Audio Section
Frequency response: 5 - 20,000 Hz ±0,5 dB
Signal-to-noise ratio: more than 90 dB
Dynamic range: more than 90 dB
Channel separation: more than 90dB (1 kHz)
Wow and Flutter: unmeasurable (dependent on accuracy of crystal oscilator)
Distortion: less than 0,006% (1 kHz, 0 dB)
Output voltage: 190 mV ( 1 kHz, -20 dB)
Number of channels: 2 (stereo)
General
System: Compact Disc Digital Audio System
Disc
Diameter: 120 mm
Thickness: 1,2 mm
Playing time: over 60 minutes
Scanning velocity: 1,2 - 1,4 m/sec.
Rotation: Counterclockwise
Signal format
Sampling frequency: 44,1 kHz
Quantisation: 16 bits linear/channel
Transfer bit rate: 4.321 M bits/sec.
Modulation system: EFM
Error correction: CIRC system
Pre-emphasis: 50/15µsec
Pickup laser: Semiconductor laser; wavelenght 0,78µm
Power requirements: 220/240 V 50/60 Hz
Power consumption: 46 watts
Dimensions (W x H x D): 420 x 140 x 330 mm (16-9/16 x 5-1/2 x 13 inches)
Weight: 12,1 kg (26 lbs. 11 oz.)
Functions
Play / Pause / index Scan / Repeat / Skip / Time Display /Pharse Dispay / Time Search / Pharse Search / Programmed Playback / Programme Check / Total Time Display

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