Pioneer PL-50/PL-50L

Commentary

A record player whose sound quality has been improved by inheriting the technology developed in the high-end PL-70.
There were 2 types, the PL-50 of the normal version and the PL-50L with the newly developed moving coil system silent lift-up function.

In order to pursue the limit of rotational accuracy, we have adopted an SH rotor type motor in which the rotor support point (bearing) located at the bottom of the motor is moved just below the turntable. By this, we have succeeded in almost matching the position of the center of gravity of the motor with that of the support point.
As a result, the reverse conical motion with the lowest part of the motor shaft as a fulcrum, which occurs due to the slight clearance between the motor shaft and bearing, which could not be prevented by the conventional structure in which the position of the center of gravity and the position of the fulcrum were greatly deviated, is eliminated, and excellent rotational characteristics are secured.
In addition, a quartz PLL DC servo Hall motor with a starting torque of 1.6kg-cm is used to eliminate load fluctuations caused by resistance received by the needle tip from the recording sound groove, and a 330kg-cm DC servo Hall motor is used to eliminate load fluctuations caused by resistance received by the needle tip from the recording sound groove.²A large turntable with a diameter of 31 cm has been adopted.
In the magnetic pole switching mechanism of the motor, three Hall elements developed by Pioneer are used, and other fine parts are finished with micron-order machining accuracy to eliminate minute noise.

A special anti-vibration agent has been applied to the back of the turntable to prevent noise that adversely affects sound quality.

In order to eliminate low-frequency resonance and achieve high sensitivity at the same time, a silicon oil braking tone arm (capable of on/off operation) is adopted.
This is a structure in which a damping fin (ring shape) is submerged in silicon oil injected into the oil cup at the upper part of the arm shaft, and damping is applied. Moreover, by cutting the tip of the fin at 45 degrees, it is designed to simultaneously apply appropriate braking in both horizontal and vertical directions.
As a result, the Q (resonance sharpness) of the low-frequency resonance is reduced, and the mechanical impedance of the tone arm is flattened. In addition, the cross-modulation distortion is greatly improved by the synergistic effect of the mass concentration method that brings the main weight of the arm closer to the rotation axis, and clear reproduction sound is realized in the entire audible band.

The arm base uses a heavy weight arm base made of die cast with a stabilizer effect, and the arm is firmly fixed to suppress partial resonance.

Long type arm with effective length of 250 mm is adopted.

A high-density cabinet with a combination of natural wood (Marble Ebony finish) and 4-layered solid board is adopted, which effectively prevents the cabinet from shaking due to the reaction of the rotational moment of the high torque motor.
The insulator is equipped with a newly developed low-center-of-gravity structure insulator that provides excellent stability against external vibrations such as howling.

By using a damping adjustment adapter sold separately, it becomes a braking level variable arm similar to PL-70, and the braking amount can be adjusted according to the compliance of the cartridge.
When mounting a cartridge with heavy weight (Orthophone SPU-GT type, etc.), it is recommended to use an exchange weight (sold separately).

The PL-50L is equipped with a silent lift-up mechanism that does not produce mechanical sounds.
This is a moving coil system that applies the operation principle of a speaker to the elevation mechanism that moves the arm up and down. It operates without contact with DC voltage.
In addition, the end position of the recording sound groove is detected by non-contact detection using a Hall element Hall element and a magnet inside the arm shaft is adopted, so that no side pressure is generated and sensitivity of the arm is not impaired.

Model Rating

Type	Cartridgeless player system
Phono Motor Section
Motor	Quartz PLL DC servo Hall motor
Drive system	Direct drive
Bearing structure	SH / rotor system
Turntable Diameter	31cm
Turntable inertia mass	330kg-cm2(including turntable seats)
Number of revolutions	33 1/3, 45 rpm
Rotational speed change	Electronic with short stroke switch
Uneven rotation	0.012% or Less (PL-50L, WRMS/FG Direct Reading Method) 0.013% or Less (PL-50, WRMS/FG Direct Reading Method) 0.023% or Less (WRMS/JIS)
S/N	78 dB or more (DIN-B) 65 dB or More (JIS)
Load variation	0% (Needle Pressure 200g or Less)
Start-up characteristic	1/3 turn or less
Starting torque	1.6kg-cm
Speed detection method	All-round integration method FG
Rotational speed deviation	Not more than 0.002%
Drift	Time drift : 0.00008% / h Temperature drift : 0.00003% / ° C.
Brake mechanism	Pure electronic
Tone Arm Section
Type	Oil braking system static balance S-shaped pipe arm
Effective length	250mm
Overhang	14mm
Tracking error	+ 2.1 °, -1.2 °
Needle pressure adjustment	Weight 1 Rotation 1g (0.1g scale)
Applicable Cartridge Dead Weight	4g ~ 13g (when using the attached shell)
Height adjustment range	+ / - 3 mm
Head shell	Aluminum Impact Press Head Shell, Dead Weight 10.5g
<General>
Attachment mechanism	Quartz lock indicator Quick stop Silent Lift Up (Electronic Type, PL-50L Only)
Semiconductors used	Quartz : 1 IC:6 Hall element : 4 (3 for PL-50) LED : 4 (3 for PL-50) Transistor : 4 Diode : 4
Pwer	100 VAC, 50Hz/60Hz
Power consumption	PL-50:8W PL-50L:13W
External dimensions	Width 490x Height 190x Depth 401 mm
Weight	15kg
Sold Separately	Damping Adjustment Adapter JP-506 (¥ 8,500) Replacement Weight JP-507 (¥ 2,400)