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

Technics SL-1800

 Technics SL-1800 Direct Drive Turntable

The SL-1800 features full Technics uncompromised direct drive performance in a simple, straightforward package. The centre ofthis sleek,attractive unit is its highly accurate One Chip IC controlled B.FG servo DC motor. This direct drive motor, which incorporates all of the design features of all Technics fine dd motors, is controlled by the unique B.FG (Back-Electromotive-Force Frequency Generator) system which utilizes the back electromotive force induced by the rotor in the stator field coils to monitor yhe platter speed. The frequency generator uses the waveform obtained as its reference and it is compared with the standard calibration frequency from the reference oscillator. In this way , a signal to correct the speed can be sent instantly whenever needed to change the motor drive current in order to maintain precise platter speed.

 This B.FG principle greatly improves speed stability and gives a shorter build-up time. It also maintains the platter speed under varying oad conditions. The above mentioned control circuitry is all contained in a fantastic One Chip IC which can perform the functions of up to 321 separate elements such as transistors, diodes and resistors. The sum of all this electronic and mechanical advancement is performance, the kind of super performance that produces the low wow and flutter figure for SL-1800 of only 0,025% (WRMS), a figure almost unsurpassed by any other turntable anywhere. Rumble is -73 dB (DIN B). Another outstanding feature of the SL-1800 is the Floating Double Isolator. This new advance fights against acoustic feedback by shielding the turntable and tonearm assembly from all outside vibrations with two separate isolators constructerd of metal springs and special vibration absorbing material.
 Additional features of the SL-1800 are a fine-scale direct reading anti-skating device, an illuminated stroboscope, independent pitch controls variable by up to 10%, sensitive gimbal suspension tonearm, viscous-damping cue arm, and detachable dust cover.
Specifications SL-1800
Turntable Section
Type:  Direct drive turntable, manual
Motor:  Electronically controlled brushless DC motor
Turntable Platter:  Aluminum diecast , 330 mm (13") diameter
Turntable Speeds:  33-1/3 and 45 rpm
Speed Change Method: Electronic change
Variable Pitch Controls:  Individual adjustment controls,  10% adjustment range
Wow and Flutter : 0,025% WRMS (JIS C5521) ±0,035% weighted, zero to peak (DIN 45507)
Rumble:  -50 dB (DIN 45539 A);  -73 dB (DIN 45539B)
Tonearm Section
Type:  Universal S-shaped tubular arm, static-balanced type, direct-reading tracking force adjustment, with anti-skating force control device, oil-damped cueing device
Effective Arm lenght:  230 mm (9-1/16")
Overhang:  15 mm (19/32")
Friction:  7 mg (horizontally and vertically)
Effective Mass:  22 g (6,0 g cartridge weight, 1,75 g stylus pressure)
Tracking Error Angle:  Within +3° (at the point of 14,5 cm or 5-45/64" record);  +1° (at the point of 5,5 cm or 3-2/16" from the centre)
Offset Angle:  21,5°
Adjustable Tracking Force:  0 - 3 g (direct-reading)
Cartridge Range:  5 - 11 g
Headshell Weight:  9,5 g
Power Supply:  AC 120 V - 240 V, 50/60 Hz
Power Consumption:  5 W
Dimensions (H x W x D):  125 x 453 x 369 mm ( 4-15/16" x 17-12/16" x 14-9/16")
Weight:  8,5 kg  (18,7 lb)

Technics Direct Drive Turntable Technology

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