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 DD-31

 Micro Seiki DD-31
Direct Drive Electro Auto Lift/Stop Complete Stereo Turntable with Rose, Ebony or Black Wooden Base and Dust Cover
 Direct Drive DC Servo Motor
Micro Seiki DD-31 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).

 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.
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)
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.
 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.
Specification DD-31
Drive System:  Direct-Drive DC Servo Motor
Speed:  33-1/3 and 45 rpm
Fine Speed Adjustment range:  ±6%
Turntable Platter:  Die-cast aluminum; 4 Strobo stripes
Diameter :  310 mm (12-1/4")
Weight :  1,2 kg (2,6 lbs)
Wow and Flutter:  less than 0,03%
Signal-to-Noise Ratio:  More than 63 dB (JIS);  75 dB (DIN-B)
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)
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

1 commento:

  1. Finally someone writes the correct s/n standard reference. Microseiki always used JIS standard without indicating it, so many peaple today (like I did) may think they were speaking about DIN B s/n and MS turntable are not so damped and quiet.