Audio Database

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A linear tracking system full auto player developed by gathering DIATONE technology.

It employs a linear tracking system in which the arm moves linearly on the record board in the same way as the cutting machine. In this system, the tangential direction of the groove is accurately traced, so tracking error and harmonic distortion can be reduced. In addition, since there is no inside force, the needle tip can contact the object, so that overall tracking capability can be improved.
A stainless steel wire is used for the drive of the moving base that fixes the tone arm. This wire combines 49 fine wires of 0.05 mm diameter with nylon coating to obtain excellent durability and flexibility.
Tracking error is detected by the potential difference between the two photodiode outputs at the rear of the arm, and the error angle is suppressed to 0.03 ° to 0.05 °.

As for the vibration caused by the movement of the arm base, the vibration generated in the moving base of the arm should be minimized. Second, the vibration generated in the moving base should not be transmitted to the needle tip.
Therefore, prior to designing, we have modeled a movement-based mechanism, established equations of motion, and conducted computer simulations to optimize the actual values of each element. We have also carefully determined the position of the optimum driving point and the position of the arm support point based on the center of impact theory.

It uses an electronically controlled full-auto mechanism. This allows all tone arm operations to be controlled simply by pressing the operation button. The circuit uses a 1-chip LSI for quick and accurate response.

It uses an automatic record size detection mechanism by applying an optical system.
In this system, the reflector emits light from obliquely above and guides the light from the turntable seat reflector to the sensor. This light is emitted or blocked depending on the size of the record and changes the output of the sensor. This output is sent to a logic circuit that automatically detects the record size.
Based on the detected record size, the needle down position and rotation speed are automatically determined.

Equipped with a quick response function, it operates while always detecting the condition of the arm lifter and arm. Therefore, it is possible to perform auto operation from any position. Thus, even when the arm is ascending or descending in auto operation, if you indicate the next new operation with the button, it will move immediately to that operation.

For button operation, feather touch type using micro switch is adopted.

Equipped with a muting mechanism to cut noise.

In order to suppress the resonance of the tone arm, a weight case and a butyl rubber damper are added to the structure of the needle pressure knob and main weight, and an anti-resonance filter is adopted. In addition, by expanding the span of the pivot, looseness of the pipe part is eliminated, and high sensitivity is achieved in both vertical and horizontal directions.

Titanium alloy is used for the material of the tone arm.

Special coated OFC (oxygen-free conductor) is used for the inner arm conductor and head shell conductor.

The turntable has a double-metal structure consisting of an aluminum die-cast turntable and a stainless steel plate. When vibration occurs on the turntable, slip occurs between the two metals and vibration energy is consumed to reduce vibration.

The turntable is driven by a quartz PLL system that controls the number of revolutions of the motor according to the reference signal of the crystal oscillator.
A high-torque DC servo motor with a precisely finished bearing mechanism is used as the drive motor.

The cabinet structure consists of a die-cast player board and a 40-mm-thick laminate fixed to it.

Weight 700g Equipped with brass disk stabilizers to promote close contact between the record board and the sheet, improving the SN ratio and resolution in the low frequency range.

Model Rating
Type Full auto player
<Turntable portion>
Drive system Direct drive system
Motor 12 Pole Quartz PLL / DC Servo Motor
Turntable 312 mm Stainless Steel Plate + Aluminum Alloy Die-cast, 2.5 kg
Inertial mass 355 kg / cm2
Number of revolutions 33 1/3, 45 rpm
Rotational speed switching system Electronic Type (Manual Switching at Irregular Rotational Speed)
Wow and flutter 0.011%WRMS
0.025% WRMS (value for rotating part only)
Signal-to-noise ratio 80dB(DIN-B)
Tone Arm Section
Format Static Balance, Universal Straight Pipe Type
Total Length 225mm
Effective length 175mm
Tracking error angle ± 0.05 ° or less
Needle pressure adjustment 0 ~ 3g Direct Reading Type (0.1g Step)
Head shell Made of magnesium alloy, 6.2g
Cartridge mounting weight range 10 ~ 16g
16g ~ 20g (when sub-weight is used)
Pwer 100 VAC, 50Hz/60Hz
Power consumption 15W
External dimensions Width 485x Height 207x Depth 413 mm
Weight 18.5kg
Attachment Overhang gauge
45 Rotation Adapter
Disk stabilizer