DIATONE LT-5V/LT-5VC

Commentary

A vertical-type record player that uses a linear tracking system.
There were 2 types, LT-5V without cartridge and LT-5VC with Diatone original cartridge MM-2 made by Orthophone.

The LT-5V has a vertical structure that is rare for a record player.
In a typical horizontal player, since the direction of vibration of the cartridge and the direction of floor vibration are the same, when mechanical vibration caused by tracing of the sound groove is converted into electrical signal by the cartridge, floor vibration is combined with the reproduced signal, which causes howling phenomenon.
On the other hand, the vertical player has a structure that is resistant to howling because the direction of floor vibration does not interfere with the direction of vibration for the cartridge to generate power.
Since the direction of the weight of the cartridge is different from the direction of the needle pressure, once the appropriate needle pressure is set, there is almost no trouble of readjusting the needle pressure even if the cartridge is replaced.

The tone arm uses a linear tracking system. In this system, the tone arm is moved horizontally along with the fulcrum, so it operates in exactly the same way as a cutting machine that cuts a sound groove in the original record.

The LT-5V consists of two parts : an optical sensor part that detects the verticality of the tone arm and a drive part that operates the tone arm based on commands from the tracking servo circuit. First, an optical sensor detects the verticality of the tone arm part and the base part, which are supported from the arm base in the direction of gravity (downward), and the output generated by the angle difference is transmitted to the tracking servo circuit. The optical sensor that quickly reacts to even slight angle difference and the tracking servo circuit with high accuracy rotate the horizontal drive motor accurately.
The optical sensor is designed to detect the verticality of the tone arm by engineering using the outputs of two highly sensitive photo-couplers.

The tone arm uses a short and straight type stainless steel arm with high rigidity and low inertial mass to reduce partial resonance and compound resonance.

In order to securely hold the record on the turntable, the record holder is equipped with a special stopper combined with a spring, and the shape of the Center shaft connected to the stopper is also modified.
In addition, by making the turntable seat into a slightly mortar shape, it is possible to firmly support even a record with a sled.

The turntable is driven by a double flywheel drive system, which combines a flywheel on the back of the turntable to improve the moment of inertia and is driven by a PLL / DC servo motor.
In addition, stable rotation is achieved by balancing each piece with high precision using a balancing machine.

The full auto mechanism adopts optical sensing logic control by LSI developed by Diatone.
In the automatic record size detection mechanism, the light emitted from the reflector reacts with the sensor corresponding to each record size. The output from the sensor is then sent to the logic circuit, which automatically detects the record size and also determines the position at which the needle drops at the start of the performance, the position at which the performance ends, and the number of revolutions.
In addition, it is equipped with a needle tip protection function, so that even if the operation button is pressed by mistake when the record board is not set on the turntable, the needle will return to the armrest without going down to the turntable.

Equipped with muting function to cut unpleasant click noise when record is inserted.

It is equipped with an optical display which shows the movement of the tone arm in real time with LED.

It is equipped with a tracking monitor to check the verticality of the tone arm. When a tracking error occurs, it is quickly caught and an LED warning is issued.

Model Rating

Type	Electronically controlled full auto player
<Turntable portion>
Drive system	Double flywheel belt drive system
Motor	PLL / DC servo motor
Turntable	304 mm Aluminum Alloy Die-cast, 1.3 kg
Inertial mass	300g-cm / S2
Number of revolutions	33 1/3, 45 rpm
Rotational speed switching system	Electronic Type (Manual Switching of Irregular Rotation Speed)
Rotational speed fine adjustment range	+ / - 3%
Wow flutter	0.045% or less (WRMS)
Signal-to-noise ratio	65 dB or more (IEC-B) 76 dB or More (DIN-B)
Tone Arm Section
Type	Static Balance Type / Universal / Straight Pipe
Total Length	223mm
Effective length	180mm
Tracking error angle	+ / - 0.1 °
Needle pressure adjustment	Direct Reading Type 0 ~ 2.5g (0.1g Step)
Head shell	LT-5V : Special Resin with Glass Fiber, 6.2g LT-5VC : Integrated Type with Cartridge (MM-2)
Cartridge mounting weight range	10 ~ 20g
<General>
Cabinet	Particle Board / Metallic Finish
Dust cover	Styrene polymers and copolymers (Removable)
Insulator	Built into the leg
Pwer	100 VAC, 50Hz/60Hz
Power consumption	14W
External dimensions	Width 466x Height 430x Depth 200 mm
Weight	11.5kg
Attachment	Overhang gauge 45 Rotation Adapter DRIVER