SONY PS-X50

Commentary

An auto-return player system designed to completely eliminate resonance.

Equipped with a simple linear BSL (slotless) motor that does not require a brush or slot. By eliminating slots that cause cogging, torque unevenness is minimized and smooth and quiet rotation is realized.
In addition, high torque is obtained due to high efficiency, and reliability and durability are also improved.

The velocity detection section of the servo system adopts a Magne-disk velocity detection method developed by introducing precision measurement technology of Sony Magne-scale.
In this method, a magnetic material is coated on the inner wall of the outer periphery of the turntable, which has a wide rotating area, and 512 wave detection signals are magnetized. The average value of these signals is detected by a multi-gap head, and control commands are sent to the servo system.
In addition, since the generated signal has a high frequency of approximately 284 Hz at 33 1/3rpm, servo compensation can be performed up to relatively high frequencies of flutter components.
In addition to the speed servo circuit, a crystal lock with a crystal oscillation phase control circuit is adopted. By phase-locking the detected signal, not only the initial drift due to self-heat generation of the main body, but also the rotational speed deviation due to voltage fluctuation due to self-heat generation and the rotational speed decrease due to needle pressure load are reduced, resulting in excellent rotational characteristics.

Uses low-capacity cord with gold-plated terminal.

The auto return mechanism uses an electronic record end detection Luminous sensor to eliminate the lateral pressure applied to the needle tip when the tone arm returns.

Uses MM type cartridge XL-25A.

The neck cylinder part, which is the joint part between the head shell and the arm pipe, holds the tip of the shell plug against the slope facing the bottom of the neck cylinder with a strong force due to the wedge effect. In addition, the locking nut is pushed forward by the reaction, and the root of the shell plug is tightened firmly from 4 directions.
As a result, two parts of the front and back are held in a ring shape by one operation, preventing mounting looseness.

The arm pipe is made of a special aluminum alloy with greatly increased rigidity, and by adopting a J-shape with high bending strength, rigidity approximately 8 times that of conventional aluminum pipe is obtained.
In addition, by adopting an integrated structure from the neck cylinder section to the bearing section, unnecessary joints are eliminated and resonance factors caused by joint looseness are eliminated.

The bearings use a Longs pan bearing shaft supported by a single straight shaft to prevent play caused by ball bearings. This minimizes movement at the operating point.
In addition, a tapered mirror finish of hardened cemented carbide with a diameter of 5 mm is used for the pivot shaft to improve contact with precision radial bearings and provide high rigidity support.

The SBMC is used for the cabinet because internal loss is larger than metal and the structure with high precision and strength can be easily obtained.

It uses a large insulator filled with gel-like high-viscoelastic material in a rubber cup.
The material filled in this insulator is very flexible, has high internal losses, and has moderate spring elasticity, which enables effective vibration absorption.
In addition, the height of this insulator can be adjusted to keep the cabinet horizontal, and the center of gravity is lowered to further improve stability.

There are PS-X50 of normal design and PS-X50W of wood-grain finish.

Model Rating

Type	Crystal Lock D. D. Auto Return Player System
<Turntable portion>
Turntable	32 cm Aluminum Die Cast 2.2 kg (Including Rubber Sheet)
Wow and flutter	0.025%wrms
Load characteristic	0% (Needle Pressure 150g)
Start-up characteristic	Within 1/2 Rotation (at 33 1/3rpm)
Drift time	0.0003% / h or less
Signal-to-noise ratio	75dB(DIN-B)
Tone Arm Section
Effective length	235mm
Total Length	330mm
Arm Height Adjustment Range	+ / - 3 mm
Needle pressure adjustment range	0 ~ 2.5g (0.1g Interval)
Shell dead weight	11.0g(SH-155)
Usable cartridge weight limit (including shell weight)	11.0 ~ 19.5g 19.0g ~ 27.5g (Auxiliary Weight Used)
Cartridge Section
Cartridge	MM Type (XL-25A)
Frequency characteristic	10 Hz to 30 kHz
Output voltage	4 mv (1 khz, 5cm/s, 45 °)
Needle	0.3x0.8 mil Diamond Oval Needle
Dead weight	5.2g
<General>
External dimensions	Width 480x Height 165x Depth 420 mm
Weight	Approx. 11.5 kg
Attachment	45 Rotation Adapter Auxiliary weight Head Shell (SH-155) Cartridge (XL-25A)