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





Fisher MT-6225 turntable

A Major Technological Advance in Turntable Engineering MT6225

 

The worlds first linear motor direct drive turntable

 

One of the problems in improving turntable performance, especially with direct drive systems, is the difficulry of reducing woa and flutter due to cogging action of the direct drive motor.

With its limited number of poles (usually 12) , a conventional direct drive system has an inherent problem, at its relatively slow operating speed, of low starting torque.

To solve these problems and improve turntable performance, Fisher has engineered the linear motor, 120 pole direct drive systems.

 


The Platter is The Motor

In effect, the platter becomes the motor of the MT6225. and Fisher's 120 pole design practically eliminates cogging action and wow and flutter - to a totally inaudible 0,03%

And the linear motor direct drive system further reduces turntable rumble to an extremely low -70 dB, so far below hearing level to be completely inaudible.

 


How it works

A continuous ring of magnetic material, containing, 120 magnetic poles, is attached to the inside bottom rim of the platter. As the platter rotates, each pole opposes one of the electromagnetic drivers on the base top. Each of the 120 poles is attracted or repelled  as it passes the driving electromagnets for smooth, stable operation.

An electronic sensing device monitors the platter's speed, and acts as a servo feedback control to maintain practically perfect speed accuracy. A built-in strobe and pitch controls are provided.

The speed accuracy of the system is independent of line voltage fluctuations.

 


The Arm

The handsomely styled Fisher MT6225 is equipped with a professional type horizontal and vertical gimbal suspended tone arm for performance commensurate with its technologically advanced design.

The arm accepts all standard cartridges. The auto-return system which returns the arm to rest at the end of a record is also an advanced design with no restraints on its lateral or vertical motion during operation.

The arm has adjustable tracking force with calibrated settings from 0,6 to 3,5 grams. There's also precise variable anti-skate, and viscous damped cueing. The MT6225 also has an aluminum alloy die cast platter, and a walnut grain vinyl veneer wood base.

 


Specifications

Motor:  Linear Direct

Drive:  Direct drive

Wow and Flutter:  0,03% (WRMS)

Rumble:  -70 dB

Speed Variation:  ±0,5%

Speed Control Range:  ±3%

Tracking Force Range:  0,6 - 3,5 grams

Platter:  Die cast aluminum

Platter Diameter:  12-15/16"

Platter Weight:  2,2 lbs

Record Speed Selector:  33-⅓ and 45 rpm

Tone-arm:  S-shape form

Resonance:  less than 10 Hz

Effective Length:  222 mm

Bearing Type

Horizontal :  Thrust

Friction Sensitivity :  0,15 gram

Vertical :  Pivot

Friction Sensitivity :  0,2 gram

Max. Tracking Error:  ±1,5°

Anti-skate:  adjustable control

Cueing:  Viscous damped

Power Requirements:  110V - 220 V Ac 50/60 Hz

Dimensions (W x H x D):  17-3/4" x 6" x 14-1/4"

Weight:  17,7 lbs

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