Audio Database

The

DIATONE DP-EC1mkII
128,000yen(around the 1978 time)

Description
 
It is the EC (electronic control) full auto player put on the market as a succeeding machine of DP-EC1.

The counterweight which built in the anti Resonance filter is adopted as the counterweight of a tone arm part. According to this prevention mechanism from a vibration, a vibration 30Hz - near 80Hz is suppressed, and the resolving power of a low-pitched sound region is raised.
Moreover, it changed to the conventional aluminum pipe and the rigid high pipe made from stainless steel is adopted as a pipe arm.

The power committed in the direction which twists a pipe, and the power committed in the direction to pull are applied to the tone arm. If the pivot is not stable at this time, such power will be applied to the needle point and sound quality will deteriorate. In order to prevent this, the span of the pivot was extended and the full-scale radial ball bearing is adopted as a level bearing. This abolishes the instability of a pipe part and the vibration is suppressed.

Two exclusive motors which became independent of the object for horizontal for - perpendicular, respectively are adopted as the drive of a tone arm.

The virgin silver line which gave special covering altogether is used for the conducting wire in an arm, and head shell conducting wire. direct-current resistance is lessened by this and the sound quality of inside and upper register is raised by improving the standup of sound.

The thing made from a Magnesium alloy is adopted as head shell.

The system which detects record size by application of an optical system without touching a record is adopted as a record size automatic detection mechanism.
The principle of this record size automatic detection mechanism glares light from the slanting upper part of a record with a reflector, and has the structure of leading light to the sensor corresponding to each record size. The light to a sensor will be intercepted according to record size, or it will glare, and the output also changes corresponding to record size. Next, the output from a sensor is sent to a logic circuit, and the size of a record is distinguished here. And the needle descent position of an auto performance, the end position of a performance, and a rotating speed are determined automatically.
Furthermore, in DP-EC1mkII, it is possible to tune the needle effect position on a record board finely by button operation.

In DP-EC1mkII, it is the design which operates while always detecting the state (a rise and descent) of an arm lifter, the level position of an arm, etc. by no contacting. For this reason, it is possible to carry out auto operation from every position.
Moreover, manual operation is possible even if it does not switch an auto manual, except when the arm is moved in auto operation.

If the quick response mechanism is carried and an arm directs new operation with a button also in a rise / descent in auto operation, it can shift to the next operation immediately.

The Quartz PLL system is adopted as rotation control of a turntable. The number of rotations of a motor is controlled by this system with the highly precise standard signal of a crystal oscillator. Moreover, 4 phase 12 pole Quartz PLL and the DC servo motor of starting torque 1.2 kg-cm are adopted as a motor.

The turntable of outside-diameter [ of 333mm ], weight [ of 1.8kg ], and inertial mass 353 g-cmS2 is adopted as a turntable.

The adhesion nature of the record was thought as important and the turntable sheet slightly designed on the earthenware mortar is adopted. The butadiene-acrylonitrile rubber sheet chosen in piles in examination over hardness, specific gravity, etc. is adopted as the quality of the material of this sheet, and it is made the value of 5mm in thickness, specific gravity 1.5, and hardness 45.

The oscillation frequency of Quartz was used for stroboscope equipment, the signal of the short pulse width for 1 / 1000 seconds was made to it, and the electronic stroboscope system which drives green LE is adopted as it.

It can be operated also where a dust cover is closed by bringing all manual operation buttons together in the front of a cabinet.

The cabinet combined wooden laminate sheets with the player board of die casting, and has adopted resinamic with weight as the quality of the material of a bottom lid.

The muting mechanism which cuts a noise is carried.

The needle point protection mechanism is carried, and when there is no record in a turntable, even if it carries out lead in, a tone arm does not get down.


Rating of a mode
Form Electronic-control full auto player
<Turntable part>
Drive system Direct-drive system
Motor 4 phase 12 pole Quartz PLL and a DC servo motor
Turntable The product made from 333mm aluminum alloy die-casting, 1.8kg
Inertial mass 353g-cm-S2
Number of rotations 33 1 / 3 or 45rpm
Number-of-rotations change system Electronic formula (it is a manual change at the time of an irregular number-of-rotations record)
Wow and flutter 0.025% or less (WRMS)
Signal to noise ratio 80dB or more (DIN-B)
<Tone arm part>
Form A static balance type and a universal S character pipe arm
Full length 320mm
Active length 227mm
Overhang 14mm
Tracking error angle + 2.9 degrees-1.5 degrees
Offset angle 22 degrees
Needle pressure adjustment Direct-reading types 0-3 g (0.1g step)
Head shell The product made from magnesium die casting, 6.2kg
Cartridge attachment weight range 11g-16.5g
16g-21.5g (at the time of sub-wait use)
<Synthesis>
Power source AC100V, 50Hz/60Hz
Power consumption 10W
Dimensions Width 470x height 150x depth of 395mm
Weight 13.5kg
Attachment Overhang gage
45 rotation adapter
Sub x weight
Driver
Cartridge spacer (two types)
Hexagon head wrench