YAMAHA YP-D71

Commentary

A highly balanced record player with three overall elements : accuracy of rotation, precision of tracing, and suppression of unwanted vibrations.

FG servo is used for the servo circuit.
The FG servo controls the rotational speed of a frequency generator (FG) that generates a frequency proportional to the rotation of the turntable. The YP-D71 has a structure that is less affected by eccentricity and pitch error of the detector because the FG that detects the rotational speed is placed around the whole circumference of the motor.

Quartz lock PLL servo is adopted to further improve the rotational accuracy enhanced by FG servo.
This quartz-locked PLL servo is a control system that eliminates the phase shift between the frequency from the FG and the reference signal generated by the crystal oscillator. As a result, the rotational accuracy of the turntable can be as high as the oscillation frequency accuracy of the crystal, and shows excellent stability against load fluctuations, voltage fluctuations, temperature fluctuations, etc.
YP-D71 has a very large lock-in torque of 500g ・ cm. There is no speed deviation against the load equivalent to 40 arms with normal needle pressure. In addition, the FG servo is designed to work in the area where the quartz lock is released, such as at the start. When the constant speed is reached, the lock indicator lights to indicate that the quartz lock is engaged.

In the YP-D71, moderate load fluctuations are improved by a quartz servo, and sudden load fluctuations are improved by the inertia mass of the turntable. In the middle part of these, the overall characteristics of the entire rotating system including the double servo and the bare characteristics of the inertia mass motor are taken into consideration and a good balance is designed to obtain the best sound.

The newly developed coreless, slotless, and DC Hall motor is used for the motor. As a result, there is very little cocking and strong torque can always be obtained. In addition, since the starting torque, which is a particular problem with coreless motors, is as large as 1 kg ・ cm, instantaneous response is also improved.

The turntable is made of 31 cm diameter aluminum die cast.
This ンテーブル has been designed to achieve a precise dynamic balance from the casting stage, and to increase the inertial mass, the mass is moved to the outer circumference, resulting in an inertial mass of 230 kg ・ cm.²For the first time.
Yamaha uses the Yamaha UR method to examine the subtle effects of the materials, processing, and finishing of the turntable on sound quality.

For the gimbal support of the tone arm, the full 4-point pivot gimbal support of the Longs pan is adopted, which reduces the fluctuation of the operating point both horizontally and vertically by making the rotating shaft into a double structure for vertical movement and horizontal movement.
The angular contact bearing that receives the pivot is supported by a rubber push to eliminate play and to prevent vibration from the cabinet from being transmitted to the arm, thereby achieving an initial motion sensitivity of 7 mg.

An aluminum S-shaped long type arm is used for the tone arm.
This arm is a long type arm that reduces S-shaped waviness, reduces tracking error, and exhibits the performance of MC cartridges with high low compliance.
The inside of the pipe arm is filled with anti-vibration material to reduce unnecessary resonance.

A zinc die-cast base is adopted for the arm base.
The arm base is strongly fixed at four points, and a zinc die-cast bracket supporting the gimbal support is fixed to the protruding 27 φ cylindrical base shaft with a tight screw.

A 6 φ NEGLEX low impedance double cylindrical cable is used for the signal cable.

It is equipped with height adjustment with 4 mm scale on 27 φ base shaft of brass sharpening, and it is compatible with various cartridges.
This height adjustment has a lock mechanism with 3-point support, and it can be fixed securely at any position.

Equipped with a thread suspension type inside four scan seller.
Rollers and thrust bearings are provided to reduce the sliding friction of the thread, and an appropriate inside for scan seller works at any position inside the inside and outside of the record.

In addition to basic measurable performances such as wow flutter and S / N ratio, we have introduced the Yamaha UR method for microscopic regions that cannot be measured. This method suppresses and controls as much as possible the vibration of all parts of the player before it reaches the needle tip of the cartridge. All parts of the player are carefully examined.

Equipped with an auto-stop mechanism that is an improved version of the one adopted in YP-D10.
In this system, the feed speed when the arm is guided into the lead-out groove at the end of the arm is non-contact detected by the combination of LED and CDs. The solenoid is operated and the power supply is turned off simultaneously.

Solid board with particle board is used for the cabinet.
In addition, it uses a 1.1 kg acrylic dust cover that is resistant to howling.

Model Rating

Type	Record player
Phono Motor Section
Drive system	Direct drive
Motor	Coreless Quartz Lock DC Hall Motor
Starting torque	1 kg / cm
Lock-in torque	500g / cm
Servo type	FG Servo + Quartz Lock PLL
Motor power supply	24 VDC / 600 mA
Turntable	31 cm Aluminum Cast, 1.8 kg (including rubber sheet)
Turntable inertia mass	230 kg / cm2(Including Rubber Sheet)
Number of revolutions	331/3, 45 rpm
SN ratio (JIS)	62 dB or more
Wow flutter	0.025%WRMS
Pitch accuracy	± 20 ppm or less
Tone Arm Section
Type	S-shaped static balance gimbal support arm
Effective arm length	242 mm (Long Arm)
Offset Angle	21 ° 15'
Tracking error	-1 ゜, + 2 ゜ 30'
Overhang	15mm
Height adjustment	+ / - 4 mm
Inside for scan seller	Thread lifting type with roller
Initial motion sensitivity	Vertical : 7 mg Horizontal : 7 mg
Arm base	Φ 27 Made of Zinc Die-cast with Brass Base Shaft
Arm lifter	Oil dump type
Weight of mounting cartridge	3g ~ 12g
Head shell	Forged Pure Aluminum (Weight 9g)
Output code	NEGLEX2496, Low Impedance Double Cylindrical Cord
<Function Part>
Auto mechanism	Photo Sensor Type Auto Up, Auto Stop
Body Part
Body Material	Particle solid board
Finish	PVC Ebony Decorative Finish
Dust cover	1.1 kg Acrylic
HINGE	Fleece Top Removable
Insulator	W-type rubber insulator
<General>
Power supply voltage	100 VAC, 50Hz/60Hz
Power consumption	9W
External dimensions	Width 470x Height 155x Depth 378 mm
Weight	11kg