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





BIC 980 turntable

 

The BIC 980 represent a considerable design achievement. For possibly the first time, engineers have embarked on a turntable design project unhampered by preconceived notions or existing peces of hardware. As a result, each of the turntable's three operation systems i tone arm, programmer and drive are new.

 

The Motor

The 24-pole, 300 rpm motor which power BIC turntables differs from motors used in automatic turntables. Its low rpm and smooth flow of power tends to eliminate the instability and vibration which create playback distortion in automatic turntables.

The BIC turntable motorat spdeed of 300 rpm it does not generate the heat/friction of high revving motors and its vibration frequencies fall below the audible range. With this low speed motor, a larger pulley can be used, minimizing tolerance and speed variation problems presented by smaller pulleys in conventional machines. The BIC motor is a synchronous unit which lock into the AC line frequency (or to its own electronically generated reference signal in the case of the 980). The coil are completely shielded, in order to keep dust and dirt may cause noise in other parts of the system

 

The Drive System

This mechanism reduces the speed of the motor shaft and transfers its turning force to the platter. Automatic turntables accomplish this through an intermediate idler wheel. BIC turntables use a belt-drive system which, until now, has been found only in fine manual and single play turntables.

 

Solid State Electronics

In the 980,speed accuracy is maintained and variable pitch adjustment is controlled by solid state circuitry. In conventional units, pitch control is accomplished through far less stable mechanical linkages.

The BIC turntable motor is a sophisticated, 24-pole synchronous unit which locks in to power line frequency, rather than line voltage. While line frequency is much more stable than voltage, it is still subject to variation in extreme cases. Therefore, the BIC 980 features a solid state electronic circuit which performs two stabilizing functions. It incorporates a Wien Bridge oscillator which generates an electronic signal that is more accurate and consistent than AC line frequency. It contains a variable speed control which allows the user to change the pitch electronically, with perfect accuracy. Electronic circuitry is the most reliable technology for assuring perfect speed stabilization. In the BIC 980 the solid state circuit board does away with mechanical pitch control linkages found in the majority of automatic turntables which invariably deteriorate with age.

Pitch Control

Pitch can be varied ±3% on the BIC 980. because the change is accomplished electronically, the control knob can be moved effortlessly. This eliminates the danger of jarring the machine while changing pitch and damaging the record or stylus.

Illuminated Stroboscope

The lighted strobe scale is fixed to the underside of the turntable and can be read easily through a window next to the control knob while a record is being played. Until now, the electronic circuitry which controls speed and pitch has been a feature of only the most sophisticated manual turntables. It has not ben available on any automatic turntable with multiple play capability. It is the one important feature distinguishing the BIC 980 from the 960. oterwise the two BIC turntables are identical.

 

The Tone Arm System

The tone arm and all controls are designed to provide exceptional performance rom the most sophisticated cartridges. They eliminate tracking force variations in multiple play - one of the major drawbacks of automatic units. They permit the user to adjust the cueing rate - a feature currently found on no other turntable.

Anti-Skating and Stylus Force Adjustment

Most of the leading manual, and automatic players have two separate scales to adjust anti-skating - one for conical and one for elliptical styli. Often these cales are difficult to read. The anti-skate controls are generally clumsy and difficult to grasp. The mechanism which makes the anti-skate compensation is normally a single spring, with a separate scale and adjustment for tracking force; this scale may or may not be positioned in direct relationship to the anti-skate control. Ideally, both controls should be lockated side by side for convenient and precise adjustment.

The tone arm is mounted on needle bearings in a precision gimbal. Atop the gimbal ring, a single calibrated scale "reads out" both anti-skate and stylus force adjustments.flanking the scale are two easy-to-grip, clearly legible control tabs. They are simple to manipulare, either one at a time or in tandem. The control lever establishing the correct setting for conical or elliptical styli is on the program panel.whenthis lever is moved to the position of the corresponding stylus type,the calibrated scale on the gimbal ring shows precise anti-skate setting.

Tracking Variation

When a series of records is played on a changer, tracking force may vary as much as.6grams from first record to last. To compensate, most changers are designed so that the middle record tracks with the correct force. Single play performance becomes a vicim of this averaging.

The pivotry of the BIC tone arm has been engineered to eliminate this compromise. Variation in tracking force from first to sixth record in multiple play is less than 0,1 gram.

 

The Cartridge Shell

This is a critical link in a tone arm system. The ultimate performance of sensitive new stereo and 4-channel cartridge/stylus combinations depends on it. The BIC cartridge shell can be fine-tuned for optimum tracking. No cartridge shell on any turntable has its advantages.

 

The Program System

This is a major innovation in turntable design. It gives the owner 7 possible manual and single-play automatic options. No other turntable offers such flexibility in the single play mode, yet simplifing the mechanism rather than making it more complex.

Not too long ago a single play turntable was the last word in playback performance. No changer or turntable with automatic features could stand close comparison with a quality manual unit. Today the situation has changed dramatically.

BIC programmed Turntables present the most critical high-fidelity enthusiast with systems-engineered instruments that meet (and in some cases exceed) the standard set by fine manual turntables. At the same time, without any sacrifice in performance, they include some very desirable automatic capabilities.

 

Specifications

Drive System

Motor:  300 rpm 24-pole synchronous , impedance protected

Drive: Long-life, precision ground, elastomer belt

Pitch Adjustment:  Electronically controlled approx. ±3%

Pitch Control Monitoring:  built-in neon bulb lighted strobe

Solid State Electronic Motor Power Supply:  stable Wien Bridge oscillator driving quadrature related power amplifiers

Start-Up Time:  full speed in less than 1/3 of a revolution

Turntable Speeds:  33-1/3 and 45 rpm

Turntable Plater:  12-inch, non-ferrous, one-piece machined die cast, balanced turntable. Weight kinetically matched to motor and drive system

Rumble (DIN):  better than -65 dB

Wow and Flutter: (WRMS):  better than 0,05%

Tone Arm System

Construction:  Tubular aluminum tone arm,in machined gimbals, mounted on die cst platform by means of a machined brass shaft.

Pivot Arrangement: 

Vertical :  Twin needle bearings pivoting in hardened ball bearing races

Horizontal :  precision ground brass shaft moving atp a lateral ball bearing race.

Bearing Friction:  less than 5 mg (horizontal), 5 - 8 mg (vertical)

Pivot to Stylus Length:  216,2 mm

Lateral tracking Erroe (Max):  0,35°/in

Effective Tone Arm mass:  18 RMS

Tone Arm Resonance:  less than 9 Hz

Tone Arm Counterweight:  one piece machined die casting, with machined knurled band and elastomeric compliant resonance/isolation damper

Stylus Overhang:  adjustable with supplied gauge

Initial 15° Vertical Tracking Angle:  user adjustable by means of adjustment screw in cartridge shell to compensate for variation in cartridge height (gauge supplied with unit)

Manual/Auto 15° Compensator:  2-position lever in shell

Stylus Track Force Range:  0 - 4 gms in 0,25 gm , calibrated increments

Tracking Force Accuracy: within 0,1 gm from 1st to 6th record

Anti-Skating Stylus Mode Selector:  lever selector for conical or elliptical types

Anti-skating Adjustment Range:   0 - 4 gms in 0,25 gm , calibrated increments

Cueing System:  Damped both directions

Cueing Rate:  user adjustable approx. 1 - 3 seconds

Cartridge Shell:  male/female 4-pin gold-plated connectors secured by locating pin and knurled locking nut

Finger Lift:  Stainless stell professional type

Minimium Tripping Force:  less than 0,15 gms

Program System

Number of recirds programmable:  1 to 6

Playing Modes:  manual; Automatic; Single; Repeat Single up to 6 times; Multiple Play up to 6 ecords

Cycle Button: feather touch actuation of all automatic modes

Geberal

Record Size:  7 and 12 inches

Tone arm Wiring Capacities:  less than 20 pF/channel

Record Support:  Reliable 2 point system, with safety support platform for automatic record handling

Shock Mounts:  4 elastomeric mounts, computer designed for the turntable

Power Requirements:  105 - 130 VAC 60 Hz , 50 Hz adaptability

Shipping Weight:  12 lbs

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