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

ADC Accutrac 4000

The world's first computerized single-play turntable. With computerized programming,  you can  hear the tracks on a record in any order you like, as often as you like, even skip the tracks you don't like. And you can do it all by remote control.

The Accutrac 4000 features a computerized control panel, a'seeing" cartridge with infra-red electro optics, a "hands-off" tone arm, electronically controlled direct drive motor, a cordless remote transmitter. LED indicator receiver and integrated circuitry to eliminate cumbersome mechanical parts. The Accutrac 4000 combines the latest breakthroughs in MOS computer circuitry and the latest advancements in direct drive technology to create the State-of -the-Art for direct drive turntables.
 The turntable with a memory
We started by replacing a lot of noisy mechanics with a neat little computer. Out came standard components in went the latest breakthrough in MOS computer circuitry.  So all Accutrac's operations are controlled and programmed far more quickly and efficiently than any other automatic turntable.  The control panel is designed for you to select up to 13 tracks in any order you want to hear them, and a 24 selection memory bank allows for programmed repeats.

The motor that keeps an eye on itself.
We replaced the conventional belts, whels and pulleys with an electronically controlled direct drive system that keeps wow and flutter to a completely inaudible 0,03% and rumble at -70 dB. The motor contains electronic speed-sensing circuits, which keep a constant eye on the accuracy of the massive 12 inch diecast turntable's speed, and instantly corrects any error.  There's also a speed tuning circuit that lets you vary the speed over 5%. A glance through the stroboscope provides a reliable speed check.
 What you hear is as incredible as what you see.
Because the Accutrac servo-motor which drives the tonearm is decoupled the instant the stylus goes into play, both horizontal and vertical friction are virtually eliminated. That means you get the most accurate tracking possible and the most faithful reproduction.
 The tonearm you never touch.
We did some more eliminating. Out went the noisy linkages that power automatic arms from the main turntable drive motor. Out went velocity-sensing mechanical arm-trip mechanisms. Out went all the clumsy cams and gears.  Instead. Accutrac's tonearm is moved by its own electro-optically controlled servo-motor. It responds instantly and silently to your programme in the turntable's memory bank.
Tracking error is minimised by the arm's 237 mm (9 ½ ") effective length, and horizontal and vertical bearing friction has been reduced to the negligible level of 5 -7 mg, due to Accutrac's new ball race and pivot system.  From the instant the stylus touches the record, the arm is totally decoupled from the servo-motor and controls, so it always track the groove with perfect freedom.
 The cartridgebthat knows where it's going.
Accutrac has the most advanced carteidge in the world.
It scans the surface of the record with a tiny bearm of light from a soild-state infra-red generator.
When the beam is focused on the record, closely spaced grooves scatter the light, while the smooth surface between the tracks reflects the arm amechanism. This system ensures that the tonearm selects the right track quickly and smoothly, while accuately guaging where it begins and ends. The low mass cartridge with its elliptical stylus, features the induced Magnet system on which ADC built its enviable reputation.   It combines a strong, accurate, signal output with a ¾ to 1 ½ gram tracking ability.
The integrated design of the tonearm and cartridge results in minimal arm mass and an ideal tonearm resonance between 8 - 10 Hz

It's all at your command.
As you see, Accutrac has some very intriguing features, quite apart from the turntable. What looks like a pocket calculator is actually a cordless command module. So you have remote control. The sculptured space-age object is the receiver for the turntable's memory bank. It's  "winking eye" tells you that your commands have been received.  Then you just sit back and enjoy what we hope you'll agree is the main attraction; the sheer excellence of the sound reproduction.

Motor Drive Sytem:  Low speeed, electronically controled, D.C. brushless direct drive motor
Speeds:  33½ and 45 RPM (electronic speed change)
Variable Pitch Controls:  ±5% range (individual control for each speed)
Wow and Flutter:  Less than 0,3% WRMS (DIN45507) ±0,042% weighted zero to peak
Rumble:  Better than -70 dB (DIN 45539B), -50 dB (DIN45539A)
Platter:  Aluminium alloy, dynamically balanced
Diameter :  306 mm
Weight :  1,4 kg
Tonearm Type:  Tubular "S" shaped, statically balanced arm, direct readout, decoupled counterweight electronically controlled cue, pause and muting operation, anti-skate control.
Effective Length:  237 mm
Overhang:  15 mm
Horizontal Friction:  5 - 7 mg
Vertical Friction:  5 - 7 mg
Offset Angle:  21°
Tracking Force:  0 - 4 g
Resonance: 8 - 10 Hz (LMA-1 cartridge)
Cartridge:  ADC LMA-1 low mass, induced-magnet (U.S. Patent 3294405), electro-optical sensing system, high energy magnet structure.
Output:  3,5 mV (5,5 cm/s)
Tracking Range:  ¾ - 1 ½ g
Frequency Response:  10 Hz - 24 kHz (±2 dB)
Separation Channel:  26 dB
Load Resistance:  47 k Ω
Stylus:  Elliptical Diamond
Remote Command:  Wireless/Infrared with LED confirm on receptor
Dimensions (W x D x H):  470 x 441 x 152 mm
Weight:  9 kg

Finish:  Teak plinth and base plate with clear perspex dust cover.

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