SONY PS-X700
¥ 99,800 (released in 1981)
Commentary
Equipped with an auto 0 balance mechanism and digital display of needle pressure, this full-auto player system further expands the potential of biotracer.
The tone arm is equipped with a biotracer which is an electronically controlled tone arm.
The tone arm consists of a microcomputer that makes hundreds of logical decisions in one thousandth of a second, speed and position sensors, and a linear motor that electronically controls all operations.
As a result, the low-frequency resonance peak can be suppressed to less than 3 dB regardless of the type of cartridge used. At the same time, the crosstalk is also improved, resulting in excellent low-frequency reproduction.
It is also robust against sleigh records, and reduces the wow and flutter sensation, resulting in improved overall sound quality.
The arm pipe is made of an aluminum alloy with increased rigidity and has a J-shaped structure with high bending strength, achieving rigidity approximately eight times that of conventional aluminum pipes.
In addition, the arm pipe to the shaft is integrated with a single straight shaft to prevent movement of the operating point and suppress unnecessary vibration of the arm.
Equipped with a contactless opto-electronic auto-disc size selector that automatically selects the record size and provides a safety function to prevent the tone arm from dropping when no record is installed.
The rotating system uses a 3-stage block consisting of a linear BSL motor, magne-disk speed detection, and quartz lock.
By adopting a linear BSL motor without brushes and slots in the DC motor, the mechanical torque change called cogging is eliminated, and quiet and smooth rotation is realized. Moreover, high torque is obtained due to high efficiency.
In the magnet-disk speed detection, a multi-gap head detects the mean value of the detection signal, which is magnetized at high density on the turntable, and detects minute changes in the rotational speed. Also, since the generated signal frequencies are relatively high, servo compensation is possible up to the higher frequencies of the flutter components.
It uses a quartz lock and utilizes the high oscillation accuracy of quartz to obtain stable rotational characteristics even with changes in ambient temperature and power supply voltage and frequency.
In order to reduce the effect of vibration, an acoustic material SBMC is used for the cabinet, and an insulator filled with a high viscosity elastic material is used for the insulator.
It employs an auto 0 balance mechanism that eliminates the need for 0 balance adjustment when the cartridge is replaced. When the tone arm is brought near the armrest, the 0 balance of the arm is automatically adjusted.
In addition, when the auto 0 balance circuit using the microcomputer does not balance the 0 balance, the digital needle pressure display flashes to give a warning.
The needle pressure can be adjusted electronically by means of a needle pressure control volume located on the front of the instrument. The needle pressure value is displayed in digital form. The needle pressure can be adjusted even while playing the record, so that the optimum value can be obtained while listening to the performance.
In addition, proper anti-skating is automatically set according to the needle pressure setting.
The tone arm's lead-in / out, up / down, and all other operations are driven by a linear motor driven by a microprocessor circuit and can be operated with the dust cover closed.
It is equipped with a queuing function, and the left and right movement of the tone arm can be controlled by a button. The tone arm moves slowly for the first 5 mm and then moves rapidly.
Equipped with an electromagnetic brake, it instantly ensures normal rotation when changing the rotational speed.
Equipped with a muting mechanism. Since it is structured so that muting is released when the needle tip is completely lowered, noise does not occur when the needle tip touches the record board.
By using the separately sold synchronized remote control unit, it is possible to play synchronized with the cassette deck.
Model Rating
| Type | Quartz Lock D. D. Full Auto Player System |
| <Turntable portion> | |
| Turntable | 32 cm Aluminum Die Cast |
| Wow and flutter | 0.015% WRMS (Rotating System) |
| Load characteristic | 0% (Needle Pressure 150g) |
| Start-up characteristic | Within 1/2 Rotation (at 33 1/3rpm) |
| Signal-to-noise ratio | 78dB(DIN-B) |
| Tone Arm Section | |
| Tone arm | Biotracer (electronically controlled tone arm) |
| Effective length | 235mm |
| Total Length | 315mm |
| Needle pressure adjustment range | 0.5g ~ 3.0g |
| Weight of attached shell | 7.7g(SH-156) |
| Usable cartridge weight range (including shell) |
9.7g ~ 16.7g 15.7g ~ 28.7g (Auxiliary Weight Small / Large Use) |
| <General> | |
| External dimensions | Width 480x Height 165x Depth 420 mm |
| Weight | 12.5kg |
| Attachment | 45 Rotation Adapter Auxiliary Weight (2 types) Head Shell (SH-156) Cartridge Mounting Screw 1 Type Dust cover |
| Sold Separately | Synchro Remote Unit RM-65 (¥ 3,000) |