What is stereo?




There are now two system of high fidelity, monophonic (monaural) and stereophonic. Monophonic is a system that starts from one microphone and is fed through a single high fidelity set. Stereophonic is a double system. Two separate microphones are placed at different sides of the orchestra and two different systems are used to keep the two signals or channels separated. Two separate speakers are used, placed on different sides of you room. Stereo is much like 3-D photography, two slightly different sound reach your ears giving you a new dimension in sound.




H.H. Scott '59





Micro Seiki DQ-41

 Micro Seiki DQ-41
Quartz Locked PLL Direct Drive Electro Auto Lift/Stop Complete Stereo Turntable, with Rose, Ebony or Black Wooden Base and Dust Cover.
The heart of any turntable are its rotation and transmission systems. In both, the quality of materials used and the precision with which they have been manufacured determine how well the turntable performs its function.
For years, the name Micro Seiki has been synonymous with turntables machined and engineered of the finest materials. Micro Seiki Turntables have been designed to advance the state-of-the-art. And win awards for elegance. These turntables are as easy to use as they are to look at.
 Electronic  Auto End-Lift and Shut-Off System
Conventional  end-of-record lift and shut-off systems use some type of mechanical link between the tonearm and trip mechanism.
Seiki turntables have a totally electronic trip system employing a Hall-Effect sensor. Since it is devoid of all mechanical appendages or links, the tonearm possesses all the qualities of a separate manual unit, including the ability to track superbly at less than 1 gram.
The concept is simple; the execution flawless. At the end of a record, the tonearm traces the run-out grooves, increaaing its speed toward the center. The Hall-Effect electronic circuit detects this speed change and generates the necessary control signals. The viscous-damped lifter is activated to raise the arm and shut off the power to the turntable. As an added protection for your records, in the event of a power failure, the arm will lift automatically, silently and smoothly.
Direct Drive DC Servo Motor
Micro Seiki DQ-41 turntables utilize a direct-driven DC servo-controlled drive motor. The advantages of this type of motor/transmissionless system are extreme speed stability and increassed torque.  Unaffected by temperature changes and voltage fluctuations, the resultant wow and flutter components are less than 0,03% WRMS and the signal-to-noise ratio greater than 63 dB JIS (75 dB DIN-B).

PLL Quartz Speed Reference
The speed of the DQ-41 is controlled by a quartz reference and phase-locked-loop. It is so accurate, it negates the need for a stroboscopic reference.
 Low-Mass Straight Tonearm with Dual Radial Bearings
A special aluminum alloy is used to give the arm its formidable strength and exceptionally low mass. Both qualities are needed to take full advantage of today's supercompliant cartridges. The straight-line geometry assures the most accurate tracking angles as well as contributing to the arm's low mass. A pair  of precision radial bearings give the arm a lateral sensitivity of only 10 milligrams.
Even the normally-overlooked signal connectors are of the constant-wipe type, insuring contact maintenance at all times.
Skating Force Cancellation
Anti-skating is provided by a precision calibrated adjustment to axactly match vertical tracking force.
 Oil Damped Cueing
Feather-light contact between stylus and record groove is provided by the oil-damped cueing system. It is silent, smooth and, at the end of a record, completely automatic.
Headshell
Thanks to the use of carbon fibres, the headshell is as light and rigid as the arm itself. It joins the arm with a semi-integrated plug-in system that utilizes thick gold-plated wiping-type contacts. Oxygen-free copper leads are used to exclude electromagnetic influences (eddy-current lossles) resulting in exceptional transmission characteristics (improved S/N ratio)

Inert Copper Coil
An inert, oxygen-free, copper coil is at the heart of the 2-MF cartridge. Electromagnetic influences (eddy current lossles) are excluded, resulting in exceptional transmission characteristics as well as an improved signal-to-noise ratio.
 Low-Impedance Circuitry
Very low impedance circuits are used throughout the 2-MF to enhance passage of the highest audio frequencies. And to insure a generous output voltage, the magnet structures are manufactured of High -Flux Alnico V.
 Low Mass Elliptical Stylus
The specially-ground elliptical diamond stylus has an extremely small moving mass. It not only has inherently good high-frequency capabilities, but excellent tracking characteristics as well.
 Crossed Yoke
A completely separated, cross-shaped yoke is utilized to isolate the left and right-channel  magnetic fields.  This novel design is responsible for the 2-MF's unusually high separation of more than 25 dB over all frequencies.
 Genuine Wood Base
One of the best acoustical dampening materials known is wood. It is used as the base material for all Micro Seiki turntables and is available in both natural rosewood and ebony finishes.
Special feet
All Micro Seiki turntable systems are equipped with specially-developed anti-feedback feet. The chart below shows a comparison between the isolation provided by conventional rubber feet and the Micro Seiki feet. As it apparent, sub-sonic resonance is greatly reduced by the Micro Seiki design.
Specifications DQ-41
Motor
Drive System:  Quartz Locked PLL Direct-Drive DC Servo Motor
Speed:  33-1/3 and 45 rpm
Turntable Platter:  Die-cast aluminum
Diameter :  330 mm (13")
Weight :  1,5 kg (3,3 lbs)
Wow and Flutter:  less than 0,025%
Signal-to-Noise Ratio:  More than 63 dB (JIS);  75 dB (DIN-B)
Tonearm
Type:  Low static mass straight type
Lateral Sensitivity:  10 mg by Dual precision Miniature Ball Bearing
Head Shell:  H707X, Light weight, mixing Carbon Fibres, Gold plated 4-pin plug-in connector
Effective length:  237 mm (9-3/8")
Overhabg:  15 mm
Maximum Tracking Error:  less than 1,5
Range of Tracking Force Adjustment:  0 -3 g
Power Supply: 100 - 120 V, 220 - 240 V 50/60 Hz
Dimensions (W x D x H):  468 x 375 x 155 mm (18-3/8" x 14-3/4" x 6-1/8")
Cartidge GAS 2-MF (Optional)
Type:  Moving Flux High Compliance Type
Frequency Response:  10 - 25,000 Hz ±2 dB
Output Voltage:  3,2 mV (1 kHz)
Channel balance:  less than 1,0 dB (1 kHz)
Channel Separation:  more than 25 dB (1 kHz)
Dc resistance:  800 Ω
Impedance: 3 k Ω (1 kHz)
Compliance:
Dynamic : 10 x 10¯⁶ cm/dyne
Static : 25 x 10¯⁶ cm/dyne
Suitable Tracking Force:  1,3  ±0,3 g
Weight:  5,4 g

Stylus Tip:  0,3 x 0,7 mill Elliptical

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